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Security

Security-improving technologies which could be deployed now

October 13, 2004

This article was contributed by John Richard Moser

Linux does not host the same applications as the more popular operating systems; it does not cater to the same host of bugs those applications provide to allow attackers to easily gain privileged access to the system. Still, if the same classes of bugs exist in Linux applications, the same problems arise. Linux is vulnerable to the same exploits as any other operating system when bugs exist to facilitate those exploits.

Most popular Linux distributions do not make use of available security technologies that would deflect a large number of these attacks. There are technologies available today that allow the maintainers of distributions such as Gentoo, Debian, or Mandrake to make the system more resilient if not virtually invulnerable to these exploitable bugs. These technologies are open source, GPL licensed solutions to the future problems that Linux will face as it gains popularity.

There are many transparent security technologies available that maintainers could use to improve the security of a Linux distribution, such as Stack Smash Protection, PaX, and Position Independent Executables (PIE). These, such as can be safely and easily integrated with any distribution to improve security without altering the users' experience or administration of the system.

Stack Smash Protection

Stack Smash Protection is a method of detection and mitigation of stack based buffer overflow bugs in programs. There are several implementations; the one focused on here is IBM's Stack Smash Protector (SSP), formerly known as ProPolice. SSP prevents stack based buffer overflow bugs from being used to exploit programs in many cases.

A fair number of security exploits begin with stack based buffer overflows. SSP rearranges local variables to put character arrays at the highest address and copies pointers passed to the function to new local variables below these arrays. This prevents a wide range of overflow based attacks. It uses a strategically placed local variable known as a "canary" or "guard value" to check for overflows.

SSP is implemented as a compiler patch to gcc. This patch alters the way functions are generated so that they check for buffer overflows. It can be used via the -fstack-protector and -fstack-protector-all switches, or by passing --enable-stack-protector to the configure script when building gcc. In either case, -fno-stack-protetctor[-all] explicitly disables the protection.

There are still some cases which SSP cannot catch, such as bugs affecting structures with vulnerable layouts; but it is definitely a powerful tool for preventing exploitation of many programming bugs. It may also expose some simple programming bugs, such as those which overflow a buffer by a few bytes. These bugs cause programs to crash during normal operation with SSP.

SSP was developed by Hiroaki Etoh and Kunikazu Yoda of the IBM Research Division, based on StackGuard. It was originally outlined in a paper by its authors. StackGuard was developed by Immunix Inc., and first appeared in 1998 or earlier. There have also been other papers examining stack smash protection techniques and implementation.

PaX

PaX is a patch to the Linux kernel source tree to implement memory protections which make certain classes of exploits difficult or impossible. Depending on architecture, PaX may have a very low or insignificant overhead. It is a powerful tool for preventing a great many potential exploits.

The Exec Shield (ES) technology contributed by Red Hat is somewhat similar to PaX; however, PaX supplies greater control over protections on individual binaries, as well as greater accuracy in its NX emulation on x86 architectures. ES has been compared to PaX on Wikipedia. Unless otherwise specified, full PaX with all features enabled except "Disallow ELF text relocations" will be discussed here.

PaX is a very feature rich technology. Instead of targeting a specific attack vector, PaX targets entire classes of exploits. Attacks using standard code injection are essentially impossible to successfully perform on a task running under full PaX restrictions; many of the more complex attacks are extremely difficult and often impossible to guarantee. Failed attacks result in the immediate termination of the program.

PaX guarantees that no memory is both writable and executable. The system administrator may deny all programs permission to use mprotect() to transition to a state where the page may be executed at any time after it could have been written to. It may emulate an NX bit to accomplish this; this is done on x86 with measurable but low overhead.

PaX also allows full Address Space Layout Randomization (ASLR). ASLR allows the stack, heap, mmap(), and even the .text of ET_EXEC executables to be mapped into randomly chosen bases in Virtual Memory (VM) space. In the absence of an information leak, an attacker would need to essentially guess at where any needed target data is in memory.

Some programs malfunction under PaX. Usually these programs expect behavior contrary to what PaX provides, and upon attempting to execute certain logic, PaX terminates them as if it had detected an exploit. PaX allows binaries to be "marked" with tools available to the system administrator to disable any individual protection supplied by PaX.

PaX was created by an anonymous author, originally supplying NX support based on an observation about the x86 architecture made by the plex86 project. Other features such as ASLR were implemented later. PaX first appeared in 2000, and was later incorporated into the grsecurity project. The PaX project supplies much documentation, and Wikipedia features an article about PaX.

Position Independent Executables

Position Independent Executables, or PIE, are executables compiled as Position Independent Code (PIC). PIC is usually slower than fixed position code; however, it can be easily relocated in memory. PIE allows the safe and efficient randomization of the base of executable binaries in VM by PaX or ES, preventing an attacker from knowing beforehand where preexisting code is in memory.

Compiling PIE binaries is done by passing gcc the -fPIC or -fPIE switches; linking them is done by passing -pie to gcc or to the linker. The -fPIE switch only works with gcc 3.4, but -fPIC will work for all. Regardless of which switch is used, the output is an executable ET_DYN binary.

Using PIE, the code in executable binaries suffers measurable overhead, the magnitude of which varies between CPU architectures. On x86, this is approximately 1%; whereas on x86_64, the overhead is approximately 0.01%. Because this overhead is not applied everywhere, it can usually be said to be negligible on any architecture in relation to PIE.

Deployment

Many security focused open source operating systems deploy these or similar technologies. OpenBSD supplies its own PaX-type system, W^X; OpenBSD also uses SSP; but apparently does not supply a PIE base. Hardened Gentoo and Adamantix supply PaX, SSP, and PIE; along with other, more visible technologies such as SELinux or RSBAC. It is left up to speculation why the most popular Linux distributions do not supply the transparent features, although there is effort to persuade Debian to use these, by the Debian: Secure by Default and the Hardened Debian projects.

Comments (25 posted)

New vulnerabilities

cyrus-sasl: remote buffer overflow

Package(s):cyrus-sasl CVE #(s):CAN-2004-0884
Created:October 7, 2004 Updated:March 16, 2005
Description: cyrus-sasl has a vulnerability involving a buffer overflow in the digestmda5.c file. A remote attacker may be able to compromise the system. Also, a local user may be able to exploit a vulnerability by using the SASL_PATH environment variable.
Alerts:
Mandrake MDKSA-2005:054 2005-03-15
SuSE SUSE-SA:2005:013 2005-03-03
Fedora-Legacy FLSA:2137 2005-02-17
OpenPKG OpenPKG-SA-2005.004 2005-01-28
Conectiva CLA-2004:889 2004-11-11
Debian DSA-568-1 2004-10-16
Debian DSA-563-3 2004-10-14
Debian DSA-563-2 2004-10-12
Debian DSA-563-1 2004-10-12
Trustix TSLSA-2004-0053 2004-10-08
Mandrake MDKSA-2004:106 2004-10-07
Red Hat RHSA-2004:546-02 2004-10-07
Gentoo 200410-05 2004-10-07

Comments (none posted)

ed: Insecure temporary file handling

Package(s):ed CVE #(s):CVE-2000-1137
Created:October 11, 2004 Updated:October 13, 2004
Description: ed insecurely creates temporary files in world-writeable directories with predictable names. Given that ed is used in various system shell scripts, they are by extension affected by the same vulnerability. A local attacker could create symbolic links in the temporary files directory, pointing to a valid file somewhere on the filesystem. When ed is called, this would result in file access with the rights of the user running the utility, which could be the root user.
Alerts:
Gentoo 200410-07 2004-10-09

Comments (none posted)

gettext: Insecure temporary file handling

Package(s):gettext CVE #(s):CAN-2004-0966
Created:October 11, 2004 Updated:March 1, 2006
Description: gettext insecurely creates temporary files in world-writeable directories with predictable names. A local attacker could create symbolic links in the temporary files directory, pointing to a valid file somewhere on the filesystem. When gettext is called, this would result in file access with the rights of the user running the utility, which could be the root user.
Alerts:
Mandriva MDKSA-2006:051 2006-02-28
Fedora-Legacy FLSA:136323 2006-01-09
Gentoo 200410-10:02 2004-10-10
OpenPKG OpenPKG-SA-2004.055 2004-12-23
Ubuntu USN-5-1 2004-10-27
Gentoo 200410-10 2004-10-10

Comments (1 posted)

mysql: several vulnerabilities

Package(s):mysql CVE #(s):CAN-2004-0835 CAN-2004-0836 CAN-2004-0837
Created:October 11, 2004 Updated:April 6, 2005
Description: Several problems have been discovered in MySQL. Oleksandr Byelkin noticed that ALTER TABLE ... RENAME checks CREATE/INSERT rights of the old table instead of the new one. (CAN-2004-0835) Lukasz Wojtow noticed a buffer overrun in the mysql_real_connect function. (CAN-2004-0836) Dean Ellis noticed that multiple threads ALTERing the same (or different) MERGE tables to change the UNION can cause the server to crash or stall. (CAN-2004-0837)
Alerts:
Ubuntu USN-109-1 2005-04-06
Fedora FEDORA-2004-530 2004-12-08
Ubuntu USN-32-1 2004-11-25
Conectiva CLA-2004:892 2004-11-18
Mandrake MDKSA-2004:119 2004-11-01
OpenPKG OpenPKG-SA-2004.045 2004-10-30
Red Hat RHSA-2004:611-01 2004-10-27
Gentoo 200410-22 2004-10-24
Red Hat RHSA-2004:569-01 2004-10-20
Red Hat RHSA-2004:597-01 2004-10-20
Debian DSA-562-1 2004-10-11

Comments (none posted)

ncompress: Buffer overflow

Package(s):compress uncompress ncompress CVE #(s):CAN-2001-1413
Created:October 11, 2004 Updated:December 14, 2004
Description: compress and uncompress do not properly check bounds on command line options, including the filename. Large parameters would trigger a buffer overflow. By supplying a carefully crafted filename or other option, an attacker could execute arbitrary code on the system. A local attacker could only execute code with his own rights, but since compress and uncompress are called by various daemon programs, this might also allow a remote attacker to execute code with the rights of the daemon making use of ncompress.
Alerts:
Red Hat RHSA-2004:536-01 2004-12-13
Gentoo 200410-08 2004-10-09

Comments (none posted)

squid: denial of service vulnerability

Package(s):squid CVE #(s):CAN-2004-0918
Created:October 7, 2004 Updated:November 8, 2004
Description: Squid has a potential denial of service vulnerability and a problem with readable passwords due to incorrect permissions on the squid.conf file.
Alerts:
Ubuntu USN-19-1 2004-11-06
Conectiva CLA-2004:882 2004-11-03
OpenPKG OpenPKG-SA-2004.048 2004-10-29
Debian DSA-576-1 2004-10-29
Mandrake MDKSA-2004:112 2004-10-21
Red Hat RHSA-2004:591-01 2004-10-20
Gentoo 200410-15 2004-10-18
Fedora FEDORA-2004-338 2004-10-13
Fedora FEDORA-2004-330 2004-10-07

Comments (none posted)

tiff: buffer overflows

Package(s):tiff CVE #(s):CAN-2004-0803
Created:October 13, 2004 Updated:April 12, 2005
Description: The tiff library contains several buffer overflows which may be exploited by way of maliciously-crafted image files. See this advisory for more information.
Alerts:
Red Hat RHSA-2005:021-01 2005-04-12
Conectiva CLA-2005:914 2005-01-06
Gentoo 200412-17 2004-12-19
Gentoo 200412-02 2004-12-05
Conectiva CLA-2004:888 2004-11-08
Slackware SSA:2004-305-02 2004-11-01
Red Hat RHSA-2004:577-01 2004-10-22
SuSE SUSE-SA:2004:038 2004-10-22
Mandrake MDKSA-2004:111 2004-10-21
Mandrake MDKSA-2004:109 2004-10-19
Debian DSA-567-1 2004-10-15
Fedora FEDORA-2004-334 2004-10-14
OpenPKG OpenPKG-SA-2004.043 2004-10-14
Gentoo 200410-11 2004-10-13

Comments (none posted)

Updated vulnerabilities

Apache mod_proxy: denial of service

Package(s):apache CVE #(s):CAN-2004-0492
Created:June 11, 2004 Updated:October 14, 2004
Description: A buffer overflow vulnerability in the apache mod_proxy module can be exploited to create a denial of service.
Alerts:
Fedora-Legacy FLSA:1737 2004-10-13
Mandrake MDKSA-2004:065 2004-06-29
Debian DSA-525-1 2004-06-24
Gentoo 200406-16 2004-06-21
OpenPKG OpenPKG-SA-2004.029 2004-06-11

Comments (none posted)

apache2: stack-based buffer overflow in ssl_util.c

Package(s):apache2 CVE #(s):CAN-2004-0488
Created:June 1, 2004 Updated:October 14, 2004
Description: A stack-based buffer overflow exists in the ssl_util_uuencode_binary function in ssl_util.c in Apache. When mod_ssl is configured to trust the issuing CA, a remote attacker may be able to execute arbitrary code via a client certificate with a long subject DN.
Alerts:
Fedora-Legacy FLSA:1888 2004-10-13
Debian DSA-532-2 2004-07-27
Debian DSA-532-1 2004-07-22
Red Hat RHSA-2004:245-01 2004-06-14
Gentoo 200406-05 2004-06-09
Slackware SSA:2004-154-01 2004-06-02
OpenPKG OpenPKG-SA-2004.026 2004-05-27
Trustix TSLSA-2004-0031 2004-06-02
Mandrake MDKSA-2004:054 2004-06-01
Mandrake MDKSA-2004:055 2004-06-01

Comments (none posted)

aspell: bounds checking problem

Package(s):aspell CVE #(s):CAN-2004-0548
Created:June 17, 2004 Updated:December 20, 2004
Description: Aspell's word-list-compress utility fails to properly check bounds when dealing with words that are more than 256 bytes long. This can lead to arbitrary code execution by an attacker.
Alerts:
Mandrake MDKSA-2004:153 2004-12-20
OpenPKG OpenPKG-SA-2004.042 2004-09-15
Gentoo 200406-14 2004-06-17

Comments (none posted)

cdrecord: failure to drop privilege

Package(s):cdrecord CVE #(s):CAN-2004-0806
Created:September 8, 2004 Updated:February 21, 2005
Description: The cdrecord utility, which is installed setuid on some distributions, fails to drop privilege before running a user-specified program.
Alerts:
Fedora-Legacy FLSA:2058 2005-02-20
Gentoo 200409-18 2004-09-14
Fedora FEDORA-2004-298 2004-09-09
Fedora FEDORA-2004-297 2004-09-09
Mandrake MDKSA-2004:091 2004-09-07

Comments (none posted)

cups: information leak

Package(s):cups CVE #(s):CAN-2004-0923
Created:October 5, 2004 Updated:October 14, 2004
Description: CUPS has an information leakage problem when printing to SMB shares requiring authentication.
Alerts:
Debian DSA-566-1 2004-10-14
Gentoo 200410-06 2004-10-09
Fedora FEDORA-2004-331 2004-10-05

Comments (none posted)

cups: denial of service

Package(s):cups cupsys CVE #(s):CAN-2004-0558
Created:September 15, 2004 Updated:October 14, 2004
Description: Versions of cups prior to 1.1.21 contain a denial of service vulnerability in their IPP implementation. A malicious UDP packet can cause cups to stop listening to the IPP port.
Alerts:
Conectiva CLA-2004:872 2004-10-14
Fedora FEDORA-2004-275 2004-09-28
Slackware SSA:2004-266-01 2004-09-22
Whitebox WBSA-2004:449-01 2004-09-20
Gentoo 200409-25 2004-09-20
SuSE SUSE-SA:2004:031 2004-09-15
Red Hat RHSA-2004:449-01 2004-09-15
Mandrake MDKSA-2004:097 2004-09-15
Debian DSA-545-1 2004-09-15

Comments (none posted)

Filename disclosure vulnerability in fam

Package(s):fam CVE #(s):CAN-2002-0875
Created:August 19, 2002 Updated:January 5, 2005
Description: "fam" (file alteration monitor) watches files and directories for changes and lets interested applications know when something happens. This package has a flaw in its group handling that blocks some legitimate operations while, at the same time, exposing the names of files that should otherwise be invisible.
Alerts:
Red Hat RHSA-2005:005-01 2005-01-05
Debian DSA-154-1 2002-08-15

Comments (none posted)

flim: insecure file creation

Package(s):flim CVE #(s):CAN-2004-0422
Created:May 5, 2004 Updated:December 16, 2004
Description: The emacs "flim" mode creates temporary files in an insecure fashion, possibly allowing a local attacker to overwrite files.
Alerts:
Fedora FEDORA-2004-546 2004-12-15
Red Hat RHSA-2004:344-01 2004-08-18
Debian DSA-500-1 2004-05-01

Comments (none posted)

Foomatic: Arbitrary command execution in foomatic-rip

Package(s):foomatic CVE #(s):CAN-2004-0801
Created:September 20, 2004 Updated:May 31, 2006
Description: There is a vulnerability in the foomatic-filters package. This vulnerability is due to insufficient checking of command-line parameters and environment variables in the foomatic-rip filter. This vulnerability may allow both local and remote attackers to execute arbitrary commands on the print server with the permissions of the spooler.
Alerts:
SuSE SUSE-SA:2006:026 2006-05-30
Fedora-Legacy FLSA:2076 2004-11-05
Conectiva CLA-2004:880 2004-10-27
Fedora FEDORA-2004-303 2004-09-21
Gentoo 200409-24 2004-09-20

Comments (none posted)

freenet6: file protection problem

Package(s):freenet6 CVE #(s):CAN-2004-0563
Created:September 30, 2004 Updated:October 6, 2004
Description: freenet6 has a protection problem which allows the username and password to be read from a configuration file.
Alerts:
Debian DSA-555-1 2004-09-30

Comments (none posted)

FreeRADIUS: denial of service

Package(s):freeradius CVE #(s):CAN-2004-0938 CAN-2004-0960 CAN-2004-0961
Created:September 22, 2004 Updated:February 2, 2005
Description: FreeRADIUS (through version 1.0.1) suffers from several denial of service vulnerabilities in its packet reception code.
Alerts:
Fedora-Legacy FLSA:2187 2005-02-01
Red Hat RHSA-2004:609-01 2004-11-12
Gentoo 200409-29 2004-09-22

Comments (none posted)

Gaim: remote code execution vulnerability

Package(s):gaim CVE #(s):CAN-2004-0500
Created:August 12, 2004 Updated:October 18, 2004
Description: The Gaim IRC client (versions 0.81 and prior) has a remote code execution vulnerability in the MSN-protocol parsing functions.
Alerts:
Fedora-Legacy FLSA:1237 2004-10-16
Whitebox WBSA-2004:400-01 2004-09-20
Slackware SSA:2004-239-01 2004-08-26
Fedora FEDORA-2004-279 2004-08-26
Fedora FEDORA-2004-278 2004-08-26
Mandrake MDKSA-2004:081 2004-08-12
SuSE SUSE-SA:2004:025 2004-08-12
Gentoo 200408-12 2004-08-12

Comments (none posted)

gtk2, gdk-pixbuf: buffer overflows

Package(s):gdk-pixbuf gtk2 CVE #(s):CAN-2004-0753 CAN-2004-0782 CAN-2004-0783 CAN-2004-0788
Created:September 15, 2004 Updated:February 25, 2005
Description: The gdk-pixbuf and gtk2 libraries contain vulnerabilities in their handling of BMP and XPM files which can lead to denial of service and, potentially, code execution attacks.
Alerts:
Fedora-Legacy FLSA:2005 2005-02-23
Conectiva CLA-2004:875 2004-10-18
Slackware SSA:2004-266-02 2004-09-22
Gentoo 200409-28 2004-09-21
Mandrake MDKSA-2004:095-1 2004-09-17
SuSE SUSE-SA:2004:033 2004-09-17
Debian DSA-549-1 2004-09-17
Red Hat RHSA-2004:447-02 2004-09-15
Debian DSA-546-1 2004-09-16
Red Hat RHSA-2004:466-01 2004-09-15
Red Hat RHSA-2004:447-01 2004-09-15
Mandrake MDKSA-2004:095 2004-09-15
Fedora FEDORA-2004-289 2004-09-15
Fedora FEDORA-2004-288 2004-09-15
Fedora FEDORA-2004-287 2004-09-15
Fedora FEDORA-2004-286 2004-09-15

Comments (none posted)

glibc: Information leak with LD_DEBUG

Package(s):glibc CVE #(s):CAN-2004-1453
Created:August 17, 2004 Updated:May 26, 2005
Description: Silvio Cesare discovered a potential information leak in glibc. It allows LD_DEBUG on SUID binaries where it should not be allowed. This has various security implications, which may be used to gain confidential information. An attacker can gain the list of symbols a SUID application uses and their locations and can then use a trojaned library taking precedence over those symbols to gain information or perform further exploitation.
Alerts:
Red Hat RHSA-2005:256-01 2005-05-18
Gentoo 200408-16 2004-08-16

Comments (1 posted)

gnome-vfs: backend script vulnerabilities

Package(s):gnome-vfs CVE #(s):CAN-2004-0494
Created:August 4, 2004 Updated:February 21, 2005
Description: Several scripts packaged with gnome-vfs, using its "extfs" capability, have security flaws. These scripts tend not to be used on many systems, but their presence can still be a threat.
Alerts:
Fedora-Legacy FLSA:1944 2005-02-20
Whitebox WBSA-2004:373-01 2004-08-19
Red Hat RHSA-2004:373-01 2004-08-04

Comments (none posted)

gtkhtml: malformed messages cause crash

Package(s):gtkhtml CVE #(s):CAN-2003-0133 CAN-2003-0541
Created:April 14, 2003 Updated:April 18, 2005
Description: GtkHTML is the HTML rendering widget used by the Evolution mail reader.

GtkHTML supplied with versions of Evolution prior to 1.2.4 contain a bug when handling HTML messages. Alan Cox discovered that certain malformed messages could cause the Evolution mail component to crash.

Alerts:
Debian DSA-710-1 2005-04-18
Mandrake MDKSA-2003:093 2003-09-18
Conectiva CLA-2003:737 2003-09-12
Red Hat RHSA-2003:264-01 2003-09-09
Mandrake MDKSA-2003:046 2003-04-15
Red Hat RHSA-2003:126-01 2003-04-14

Comments (none posted)

apache2: IPv6 denial of service

Package(s):httpd apache2 CVE #(s):CAN-2004-0747 CAN-2004-0751 CAN-2004-0786 CAN-2004-0809
Created:September 15, 2004 Updated:October 6, 2004
Description: Apache2 contains an integer error in the apr_uri_parse() function when handling IPv6 addresses. The result is a code execution vulnerability on BSD systems, and a denial of service vulnerability under Linux.
Alerts:
Debian DSA-558-1 2004-10-06
Trustix TSLSA-2004-0047 2004-09-16
Mandrake MDKSA-2004:096 2004-09-15
Gentoo 200409-21 2004-09-16
Fedora FEDORA-2004-308 2004-09-16
Fedora FEDORA-2004-307 2004-09-16
SuSE SUSE-SA:2004:032 2004-09-15
Red Hat RHSA-2004:463-01 2004-09-15

Comments (none posted)

imagemagick: buffer overflow vulnerability

Package(s):imagemagick CVE #(s):CAN-2004-0827
Created:September 16, 2004 Updated:November 30, 2004
Description: The ImageMagick graphics library has several buffer overflow vulnerabilities that allow an attacker to crash the reading process by creating mal-formed video or image files in the AVI, BMP, or DIB format.
Alerts:
Ubuntu USN-35-1 2004-11-30
Ubuntu USN-7-1 2004-10-27
Red Hat RHSA-2004:480-01 2004-10-20
Red Hat RHSA-2004:494-01 2004-10-20
Mandrake MDKSA-2004:102 2004-09-22
Debian DSA-547-1 2004-09-16

Comments (none posted)

imlib2: buffer overflows

Package(s):imlib2 CVE #(s):CAN-2004-0802 CAN-2004-0817
Created:September 8, 2004 Updated:October 26, 2005
Description: The imlib2 library contains buffer overflows in the BMP handling code.
Alerts:
Debian DSA-548-2 2005-10-26
Conectiva CLA-2004:870 2004-09-28
Debian DSA-552-1 2004-09-22
Debian DSA-548-1 2004-09-16
Red Hat RHSA-2004:465-01 2004-09-15
Gentoo 200409-12 2004-09-08
Fedora FEDORA-2004-301 2004-09-09
Fedora FEDORA-2004-300 2004-09-09
Mandrake MDKSA-2004:089 2004-09-07

Comments (none posted)

iproute: local denial of service

Package(s):iproute net-tools CVE #(s):CAN-2003-0856
Created:November 25, 2003 Updated:December 14, 2004
Description: The iproute utility is susceptible to spoofed netlink messages sent by local users, with the result that denial of service attacks are possible.
Alerts:
Mandrake MDKSA-2004:148 2004-12-13
Fedora FEDORA-2004-154 2004-06-03
Fedora FEDORA-2004-115 2004-05-11
Debian DSA-492-1 2004-04-18
Gentoo 200404-10 2004-04-09
Red Hat RHSA-2003:316-01 2003-11-24

Comments (none posted)

kernel information leak

Package(s):kernel CVE #(s):CAN-2004-0415
Created:August 3, 2004 Updated:October 26, 2004
Description: Paul Starzetz discovered flaws in the Linux kernel when handling file offset pointers. These consist of invalid conversions of 64 to 32-bit file offset pointers and possible race conditions. A local unprivileged user could make use of these flaws to access large portions of kernel memory. Note that this vulnerability affects all 2.4 kernels through 2.4.26 and 2.6 kernels through 2.6.7.

A fix for this problem was added to the fifth 2.4.27 release candidate.

Alerts:
Conectiva CLA-2004:879 2004-10-26
Fedora-Legacy FLSA:1804 2004-10-18
Mandrake MDKSA-2004:087 2004-08-26
Gentoo 200408-24 2004-08-25
Whitebox WBSA-2004:413-01 2004-08-19
Red Hat RHSA-2004:327-01 2004-08-18
Fedora FEDORA-2004-251 2004-08-10
Trustix TSLSA-2004-0041 2004-08-09
SuSE SUSE-SA:2004:024 2004-08-09
Red Hat RHSA-2004:413-01 2004-08-03
Red Hat RHSA-2004:418-01 2004-08-03
Fedora FEDORA-2004-247 2004-08-03

Comments (none posted)

kernel-utils: setuid vulnerability

Package(s):kernel-utils CVE #(s):CAN-2003-0019
Created:February 7, 2003 Updated:January 21, 2005
Description: The kernel-utils package contains several utilities that can be used to control the kernel or machine hardware. In Red Hat Linux 8.0 this package contains user mode linux (UML) utilities.

The uml_net utility in kernel-utils packages with Red Hat Linux 8.0 was incorrectly shipped setuid root. This could allow local users to control certain network interfaces, add and remove arp entries and routes, and put interfaces in and out of promiscuous mode.

All users of the kernel-utils package should update to these packages that contain a version of uml_net that is not setuid root.

Alternatively, as a work-around to this vulnerability issue the following command as root:

chmod -s /usr/bin/uml_net

Alerts:
Red Hat RHSA-2003:056-08 2003-02-07

Comments (none posted)

lha: stack-based buffer overflow

Package(s):lha CVE #(s):CAN-2004-0769 CAN-2004-0771 CAN-2004-0694 CAN-2004-0745
Created:September 2, 2004 Updated:October 14, 2004
Description: The lha archiving and compression utility has a stack-based buffer overflow vulnerability. A modified archive could allow an attacker to execute code when a victim extracts or test the archive.
Alerts:
Fedora-Legacy FLSA:1833 2004-10-13
Whitebox WBSA-2004:323-01 2004-09-20
Gentoo 200409-13 2004-09-08
Fedora FEDORA-2004-295 2004-09-08
Fedora FEDORA-2004-294 2004-09-08
Red Hat RHSA-2004:323-01 2004-09-01

Comments (none posted)

libpng: multiple vulnerabilities

Package(s):libpng CVE #(s):CAN-2002-1363 CAN-2004-0597 CAN-2004-0598 CAN-2004-0599
Created:August 4, 2004 Updated:February 10, 2005
Description: There is yet another set of holes in libpng, versions 1.2.5 and prior, which can be exploited by a malicious image file; see this advisory from Chris Evans or this CERT advisory for details.
Alerts:
Fedora-Legacy FLSA:1943 2005-02-08
Red Hat RHSA-2004:421-01 2004-08-04
Gentoo 200408-22 2004-08-23
Whitebox WBSA-2004:402-01 2004-08-19
Mandrake MDKSA-2004:082 2004-08-12
Slackware SSA:2004-223-01 2004-08-09
Slackware SSA:2004-223-02 2004-08-07
Slackware SSA:2004-222-01b 2004-08-10
Slackware SSA:2004-222-01 2004-08-07
Conectiva CLA-2004:856 2004-08-06
Trustix TSLSA-2004-0040 2004-08-05
Gentoo 200408-03 2004-08-05
Debian DSA-536-1 2004-08-04
Mandrake MDKSA-2004:079 2004-08-04
SuSE SUSE-SA:2004:023 2004-08-04
Red Hat RHSA-2004:402-01 2004-08-04
OpenPKG OpenPKG-SA-2004.035 2004-08-04

Comments (1 posted)

libxpm4: stack and integer overflows

Package(s):libxpm4 CVE #(s):CAN-2004-0687 CAN-2004-0688
Created:September 16, 2004 Updated:February 14, 2005
Description: There are several stack and integer overflow bugs in the libXpm code of XFree86 that may be used for a denial of service.
Alerts:
Conectiva CLA-2005:924 2005-02-14
Red Hat RHSA-2005:004-01 2005-01-12
Red Hat RHSA-2004:537-01 2004-12-02
Ubuntu USN-27-1 2004-11-17
Mandrake MDKSA-2004:124 2004-11-04
Debian DSA-561-1 2004-10-11
Gentoo 200410-09 2004-10-09
Debian DSA-560-1 2004-10-07
Red Hat RHSA-2004:479-01 2004-10-06
Red Hat RHSA-2004:478-01 2004-10-04
Gentoo 200409-34 2004-09-27
SuSE SUSE-SA:2004:034 2004-09-17
Mandrake MDKSA-2004:099 2004-09-15
Mandrake MDKSA-2004:098 2004-09-15

Comments (none posted)

logcheck: symlink vulnerability

Package(s):logcheck CVE #(s):CAN-2004-0404
Created:April 21, 2004 Updated:December 22, 2004
Description: The logcheck utility handles temporary files in an unsafe way, possibly allowing local attackers to overwrite files.
Alerts:
Mandrake MDKSA-2004:155 2004-12-22
Debian DSA-488-1 2004-04-16

Comments (none posted)

Midnight Commander: extfs vfs vulnerability

Package(s):mc CVE #(s):CAN-2004-0494
Created:September 2, 2004 Updated:January 5, 2005
Description: Midnight Commander has a vfs vulnerability with shell quoting in extfs perl scripts.
Alerts:
Red Hat RHSA-2004:464-02 2005-01-05
Red Hat RHSA-2004:464-01 2004-09-15
Fedora FEDORA-2004-273 2004-09-01
Fedora FEDORA-2004-272 2004-09-01

Comments (none posted)

mikmod: buffer overflow

Package(s):mikmod CVE #(s):CAN-2003-0427
Created:June 16, 2003 Updated:June 16, 2005
Description: Ingo Saitz discovered a bug in mikmod whereby a long filename inside an archive file can overflow a buffer when the archive is being read by mikmod.
Alerts:
Fedora FEDORA-2005-405 2005-06-16
Red Hat RHSA-2005:506-01 2005-06-13
Fedora FEDORA-2005-404 2005-06-09
Gentoo 200307-01 2003-07-02
Debian DSA-320-1 2003-06-13

Comments (none posted)

mozilla products: arbitrary code execution and other vulnerabilities

Package(s):mozilla firefox thunderbird CVE #(s):CAN-2004-0902 CAN-2004-0903 CAN-2004-0904 CAN-2004-0905 CAN-2004-0908
Created:September 20, 2004 Updated:January 13, 2005
Description: Several vulnerabilities exist in the Mozilla web browser and derived products, the most serious of which could allow a remote attacker to execute arbitrary code on an affected system. See the CERT advisory for details.
Alerts:
Gentoo 200501-03 2005-01-05
Fedora-Legacy FLSA:2089 2004-10-27
Conectiva CLA-2004:877 2004-10-22
Mandrake MDKSA-2004:107 2004-10-19
SuSE SUSE-SA:2004:036 2004-10-06
Red Hat RHSA-2004:486-01 2004-09-30
Slackware SSA:2004-266-03 2004-09-22
Gentoo 200409-26 2004-09-20

Comments (none posted)

mpg123: buffer overflow bug

Package(s):mpg123 CVE #(s):CAN-2004-0805
Created:September 16, 2004 Updated:January 11, 2005
Description: The mpg123 audio playing utility has a buffer overflow bug that may allow arbitrary execution of code.
Alerts:
Gentoo 200501-14 2005-01-10
Debian DSA-564-1 2004-10-13
Mandrake MDKSA-2004:100 2004-09-22
Gentoo 200409-20 2004-09-16

Comments (none posted)

mpg321: format string vulnerability

Package(s):mpg321 CVE #(s):CAN-2003-0969
Created:January 6, 2004 Updated:March 28, 2005
Description: A vulnerability was discovered in mpg321, a command-line mp3 player, whereby user-supplied strings were passed to printf(3) unsafely. This vulnerability could be exploited by a remote attacker to overwrite memory, and possibly execute arbitrary code. In order for this vulnerability to be exploited, mpg321 would need to play a malicious mp3 file (including via HTTP streaming).
Alerts:
Gentoo 200503-34 2005-03-28
Debian DSA-411-1 2004-01-05

Comments (none posted)

net-acct: temporary file vulnerability

Package(s):net-acct CVE #(s):CAN-2004-0851
Created:October 6, 2004 Updated:October 6, 2004
Description: Net-acct (an IP accounting daemon) version 0.71 suffers from a temporary file vulnerability.
Alerts:
Debian DSA-559-1 2004-10-06

Comments (none posted)

netkit-telnet: invalid free pointer

Package(s):netkit-telnet CVE #(s):CAN-2004-0911
Created:October 4, 2004 Updated:March 28, 2005
Description: Michal Zalewski discovered a bug in the netkit-telnet server (telnetd) whereby a remote attacker could cause the telnetd process to free an invalid pointer. This causes the telnet server process to crash, leading to a straightforward denial of service (inetd will disable the service if telnetd is crashed repeatedly), or possibly the execution of arbitrary code with the privileges of the telnetd process (by default, the 'telnetd' user).
Alerts:
Ubuntu USN-101-1 2005-03-28
Debian DSA-556-2 2004-10-18
Debian DSA-569-1 2004-10-18
Debian DSA-556-1 2004-10-02

Comments (none posted)

netpbm: insecure temporary files

Package(s):netpbm CVE #(s):CAN-2003-0924
Created:January 19, 2004 Updated:December 29, 2004
Description: netpbm is graphics conversion toolkit made up of a large number of single-purpose programs. Many of these programs were found to create temporary files in an insecure manner, which could allow a local attacker to overwrite files with the privileges of the user invoking a vulnerable netpbm tool.
Alerts:
Conectiva CLA-2004:909 2004-12-29
Gentoo 200410-02 2004-10-04
Mandrake MDKSA-2004:011-1 2004-09-27
Whitebox WBSA-2004:031-01 2004-02-12
Mandrake MDKSA-2004:011 2004-02-11
Red Hat RHSA-2004:030-01 2004-02-05
Fedora FEDORA-2004-068 2004-02-06
Red Hat RHSA-2004:031-01 2004-01-22
Debian DSA-426-1 2004-01-18

Comments (1 posted)

OpenOffice: information disclosure

Package(s):openoffice.org CVE #(s):CAN-2004-0752
Created:September 15, 2004 Updated:October 20, 2004
Description: OpenOffice.org contains a temporary file handling vulnerability which can allow one local user to read the contents of another user's open files.
Alerts:
Gentoo 200410-17 2004-10-20
Mandrake MDKSA-2004:103 2004-09-27
Red Hat RHSA-2004:446-01 2004-09-15

Comments (none posted)

openssh: timing attack leads to information disclosure

Package(s):openssh CVE #(s):CAN-2003-0190
Created:May 2, 2003 Updated:November 30, 2004
Description: From the advisory: "During a pen-test we stumbled across a nasty bug in OpenSSH-portable with PAM support enabled (via the --with-pam configure script switch). This bug allows a remote attacker to identify valid users on vulnerable systems, through a simple timing attack. The vulnerability is easy to exploit and may have high severity, if combined with poor password policies and other security problems that allow local privilege escalation."
Alerts:
Ubuntu USN-34-1 2004-11-30
OpenPKG OpenPKG-SA-2003.035 2003-08-06
Red Hat RHSA-2003:222-01 2003-07-29
Gentoo 200305-02 2003-05-13
Gentoo 200305-01 2002-03-05

Comments (1 posted)

OpenSSL: denial of service vulnerabilities

Package(s):OpenSSL CVE #(s):CAN-2004-0081 CAN-2003-0851
Created:March 17, 2004 Updated:November 2, 2005
Description: Versions 0.9.7a-c of the OpenSSL library suffer from two denial of service vulnerabilities; see the version 0.9.7d release announcement for details.
Alerts:
Red Hat RHSA-2005:830-00 2005-11-02
Red Hat RHSA-2005:829-00 2005-11-02
Fedora FEDORA-2005-1042 2005-10-31
Fedora-Legacy FLSA:1395 2004-05-08
Conectiva CLA-2004:834 2004-03-31
Whitebox WBSA-2004:084-01 2004-03-23
Red Hat RHSA-2004:084-01 2004-03-23
Fedora FEDORA-2004-095 2004-03-19
Whitebox WBSA-2004:120-01 2004-03-22
Trustix TSLSA-2004-0012 2004-03-17
Slackware SSA:2004-077-01 2004-03-17
Red Hat RHSA-2004:121-01 2004-03-17
OpenPKG OpenPKG-SA-2004.007 2004-03-18
Gentoo 200403-03 2004-03-17
Debian DSA-465-1 2004-03-17
Netwosix NW-2004-0005 2004-03-17
Mandrake MDKSA-2004:023 2004-03-17
SuSE SuSE-SA:2004:007 2004-03-17
Red Hat RHSA-2004:120-01 2004-03-17
Red Hat RHSA-2004:119-01 2004-03-17
EnGarde ESA-20040317-003 2004-03-17

Comments (1 posted)

pavuk: buffer overflow

Package(s):pavuk CVE #(s):CAN-2004-0456
Created:June 30, 2004 Updated:November 11, 2004
Description: Versions of the pavuk web spider through 0.9.28-r1 contain a buffer overflow which could be exploited by a hostile server.
Alerts:
Gentoo 200411-19 2004-11-10
Debian DSA-527-1 2004-07-03
Gentoo 200406-22 2004-06-30

Comments (none posted)

php: remotely exploitable memory errors

Package(s):php CVE #(s):CAN-2004-0594
Created:July 14, 2004 Updated:February 7, 2005
Description: Stefan Esser has issued an advisory regarding a remotely exploitable hole in PHP (through version 4.3.7). If the memory_limit feature is in use (as it should be, to prevent denial of service attacks), allocation failures can be forced at highly inopportune times, and those failures can be exploited to execute arbitrary code. The exploit is described as "quite easy," and it can be done regardless of whether Apache1 or Apache2 is in use. Upgrading to PHP 4.3.8 fixes the problem; yesterday's PHP 5.0 release also contains the fix (but the final release candidate did not).
Alerts:
Debian DSA-669-1 2005-02-07
Whitebox WBSA-2004:392-01 2004-08-19
Fedora FEDORA-2004-223 2004-07-23
Fedora FEDORA-2004-222 2004-07-23
OpenPKG OpenPKG-SA-2004.034 2004-07-22
Slackware SSA:2004-202-01 2004-07-20
Debian DSA-531-1 2004-07-20
Red Hat RHSA-2004:392-01 2004-07-19
Red Hat RHSA-2004:395-01 2004-07-19
Conectiva CLA-2004:847 2004-07-16
SuSE SUSE-SA:2004:021 2004-07-16
Mandrake MDKSA-2004:068 2004-07-14
Gentoo 200407-13 2004-07-15
tinysofa TSSA-2004-013 2004-07-14

Comments (none posted)

php: information disclosure and file upload vulnerabilities

Package(s):php CVE #(s):
Created:October 6, 2004 Updated:October 6, 2004
Description: Versions of PHP prior to 4.3.9 suffer from vulnerabilities which can disclose the contents of random memory to an attacker and allow uploads of files to any location writable by the web server.
Alerts:
Gentoo 200410-04 2004-10-06

Comments (none posted)

PuTTY: pre-authentication arbitrary code execution problem

Package(s):putty CVE #(s):
Created:August 5, 2004 Updated:October 28, 2004
Description: PuTTY, a telnet and SSH client, contains a vulnerability that can allow an SSH server to execute arbitrary code on a connecting client.
Alerts:
Gentoo 200410-29 2004-10-27
Gentoo 200408-04 2004-08-05

Comments (none posted)

python: buffer overflow

Package(s):python CVE #(s):CAN-2004-0150
Created:March 10, 2004 Updated:October 11, 2004
Description: Python (versions 2.2 and 2.2.1 only) has a buffer overflow in the getaddrinfo() function which can be exploited by a malformed IPv6 address.
Alerts:
Debian DSA-458-3 2004-10-10
Gentoo 200409-03 2004-09-02
Debian DSA-458-2 2004-08-31
Mandrake MDKSA-2004:019 2004-03-09
Debian DSA-458-1 2004-03-09

Comments (none posted)

qt3: BMP image parser heap overflow

Package(s):qt3/qt3-non-mt/qt3-32bit/qt3-static CVE #(s):CAN-2004-0691 CAN-2004-0692 CAN-2004-0693
Created:August 19, 2004 Updated:May 15, 2005
Description: A heap overflow in the qt3 BMP image format parser in Qt versions prior to 3.3.3 may allow remote code execution.
Alerts:
Fedora-Legacy FLSA:152763 2005-05-12
Conectiva CLA-2004:866 2004-09-22
Whitebox WBSA-2004:414-01 2004-09-20
Debian DSA-542-1 2004-08-30
Fedora FEDORA-2004-271 2004-08-23
Fedora FEDORA-2004-270 2004-08-23
Gentoo 200408-20 2004-08-22
Red Hat RHSA-2004:414-01 2004-08-20
Mandrake MDKSA-2004:085 2004-08-18
SuSE SUSE-SA:2004:027 2004-08-19

Comments (none posted)

rp-pppoe, pppoe: missing privilege dropping

Package(s):rp-pppoe, pppoe CVE #(s):CAN-2004-0564
Created:October 4, 2004 Updated:November 14, 2005
Description: Max Vozeler discovered a vulnerability in pppoe, the PPP over Ethernet driver from Roaring Penguin. When the program is running setuid root (which is not the case in a default Debian installation), an attacker could overwrite any file on the file system.
Alerts:
Fedora-Legacy FLSA:152794 2005-11-14
Mandrake MDKSA-2004:145 2004-12-06
Debian DSA-557-1 2004-10-04

Comments (none posted)

rsync: path-sanitizing bug

Package(s):rsync CVE #(s):CAN-2004-0792
Created:August 16, 2004 Updated:November 1, 2004
Description: This August 2004 rsync advisory reports that there is a path-sanitizing bug that affects daemon mode in all recent rsync versions (including 2.6.2) but only if chroot is disabled. It does NOT affect the normal send/receive filenames that specify what files should be transferred (this is because these names happen to get sanitized twice, and thus the second call removes any lingering leading slash(es) that the first call left behind). It does affect certain option paths that cause auxilliary files to be read or written.
Alerts:
Conectiva CLA-2004:881 2004-11-01
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