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Security

A decline in email spam?

By Jake Edge
July 7, 2011

One of the biggest internet irritants over the last decade or two clearly has to be email spam. It has collectively taken billions of hours of users' time to deal with, consumed countless terabytes of wasted disk space, burned bandwidth better spent on kitten videos, and used up vast quantities of developer time to come up with new ways to filter it out or come up with other technological fixes. So, recent reports that email spam is in decline are certainly welcome, if true, but even with the 90% decline over the last year that is being reported, the amount of spam being sent is still staggering—and likely to be with us for a long time to come.

I haven't heard friends and colleagues extolling a reduction in the amount of spam they receive but, as they say, the plural of anecdote is not data. One would think that such a precipitous drop would be noticed by email users, however. In any case, Cisco, Symantec, and others are reporting numbers like 34 billion spam emails per day for April, down from 300 billion in mid-2010. That's an enormous drop in the volume, even if 34 billion a day is still huge. Without any hard data to the contrary, some significant drop-off in spam volume is a reasonable conclusion—and one worth exploring a little bit.

Spam has always been driven by its economics. In the early days, it cost almost nothing to send out huge volumes of email, and the chances of getting caught and meaningfully punished were quite small. That led to various "spam kings" who made outrageous amounts of money by spamming the world. If sending spam is, for all intents and purposes, free, you don't need a very high response rate to the pitch in order to bring in substantial sums. But that led to a backlash.

Users quickly tired of digging through email that was 90-100% spam, ISPs got smarter about not allowing their systems to be used for spam transmission, and, eventually, governments decided to ramp up the punishment side of the equation. Spam filtering became ubiquitous, blacklists that identified sites sending spam started to pop up, prosecutions of those sending spam were successful to some extent, and so on. The cost of sending spam has risen substantially over the years.

That's not to say that there aren't some folks still making lots of money sending spam, but these days there are bigger phish (so to speak) to fry. The most lucrative schemes today don't rely on sending enormous volumes of email and are more targeted instead.

It would be nice to think that users are getting a bit more sophisticated—or just running out of body parts to enlarge. It's hard to say whether that's true or not, but, even with the growth in new internet users, one might hope that the negative publicity about internet scams is making users more wary. Unfortunately, one doesn't have to search very far to find a news item about someone taken in by email claiming to be from a foreigner who wants to send them "EIGHT BILLION DOLLARS". So, it's probably overoptimistic to attribute much of the spam volume drop to users being less likely to respond to the pitch.

Filtering has certainly gotten better over the years, and moved from something users had to fiddle with to "the cloud" (or at least their ISP). Spammers have routinely run their emails through tools like SpamAssassin to try to evade filters, but there are limits to that approach, especially when individual Bayesian filters are factored in. It's difficult for even gullible users to respond to a spam pitch they don't see, so filtering has likely done much to reduce the effectiveness of spam.

Another factor that may be at play here is that many folks have moved beyond email for much or all of their communication. Text messages, instant messaging, and the services provided by various walled gardens (e.g. Facebook, Twitter) have replaced email for a lot of people, especially those darn kids, these days. Spam has, of course, evolved to assail those media as well. That kind of spam is not reflected in these recent statistics, however.

So, while it is somewhat heartening to hear that some folks are probably receiving less email spam, it's unlikely that it's really going to change things for most people. Users will still need filtering, ISPs and governments will still need to be vigilant, and clicking on links in dodgy email will still be a bad idea. While likely mind-numbing, seven days of reading all the email you receive might also prove somewhat eye-opening.

Like it or not, spam has become part of our culture. From the origin of the "spam" name to the various terms for different kinds of spam (419 spam, phishing, etc.), spam has used and been used by internet culture. Over the years, various folks have imagined horrible demises for spammers—e.g. Rule 34—usually involving the products they pitch in some bizarre fashion. So, at least we can get a chuckle from spam now and again, even as it is an extremely annoying—sometimes dangerous—phenomenon. In fact, it would be nice if junk (snail) mail filters were even half as good as email filters are these days.

Comments (42 posted)

Brief items

Security quotes of the week

The researchers tallied the losses from fake AV [anti-virus] victims of the three operations: One firm's victims lost $11 million; the second, $5 million; and the third, $116.9 million. That meant about $45 million per year in income for AV1, $3.8 million for AV2, and $48.4 million for AV3. The AV operators charged their victims $49.95 to 69.95 for six-month licenses, and $79.95 to $89.95 for lifetime licenses.
-- Dark Reading on a report [PDF] on fake anti-virus companies

You are supposed to be protecting us, but at this point you are ... terrorizing us. You have arbitrary and capricious rules that you apply without the aid of common sense. I mean where did TSA officials get their training, Abu Ghraib?
-- Elie Mystal

People get USB sticks all the time. The problem isn't that people are idiots, that they should know that a USB stick found on the street is automatically bad and a USB stick given away at a trade show is automatically good. The problem is that the OS trusts random USB sticks. The problem is that the OS will automatically run a program that can install malware from a USB stick. The problem is that it isn't safe to plug a USB stick into a computer.

Quit blaming the victim. They're just trying to get by.

-- Bruce Schneier

The ongoing WikiLeaks fight is a wake-up call for anyone who's been blithely relying on the cloud. It only took a few days for WikiLeaks to become a digital refugee, slogging from one service provider to the next, trying to find someone with enough backbone to keep it online in the face of legal threats, political intervention, and mysterious traffic-floods from persons or governments unknown.
-- Cory Doctorow

Comments (5 posted)

Vsftpd backdoor discovered in source code (The H)

The H reports that the vsftpd download site has been compromised and version 2.3.4 contains a back door. "The bad tarball included a backdoor in the code which would respond to a user logging in with a user name ':)' by listening on port 6200 for a connection and launching a shell when someone connects." Anybody who downloaded and installed that version should be looking to replace it quickly.

Comments (37 posted)

Top 25 Most Dangerous Software Errors

Each year, the SANS Institute and MITRE's Common Weakness Evaluation (CWE) project team up to create a list of the most dangerous software errors. The 2011 edition has just been released with SQL injection followed by OS command injection topping the list. "The Top 25 list is a tool for education and awareness to help programmers to prevent the kinds of vulnerabilities that plague the software industry, by identifying and avoiding all-too-common mistakes that occur before software is even shipped. Software customers can use the same list to help them to ask for more secure software. Researchers in software security can use the Top 25 to focus on a narrow but important subset of all known security weaknesses. Finally, software managers and CIOs can use the Top 25 list as a measuring stick of progress in their efforts to secure their software."

Comments (none posted)

New vulnerabilities

bind: denial of service

Package(s):bind9 bind CVE #(s):CVE-2011-2464 CVE-2011-2465
Created:July 6, 2011 Updated:November 18, 2011
Description: Multiple versions of the bind9 name server are affected by two remote denial of service vulnerabilities. See the ISC advisories for CVE-2011-2464 and CVE-2011-2465 for more information.
Alerts:
Oracle ELSA-2011-1458 2011-11-18
Slackware SSA:2011-224-01 2011-08-15
Fedora FEDORA-2011-9127 2011-07-08
Mandriva MDVSA-2011:115 2011-07-20
SUSE SUSE-SU-2011:0759-1 2011-07-19
openSUSE openSUSE-SU-2011:0788-1 2011-07-19
Fedora FEDORA-2011-9146 2011-07-08
Scientific Linux SL-bind-20110707 2011-07-07
Slackware SSA:2011-189-01 2011-07-11
SUSE SUSE-SA:2011:029 2011-07-08
CentOS CESA-2011:0926 2011-07-07
Red Hat RHSA-2011:0926-01 2011-07-07
Debian DSA-2272-1 2011-07-05
Ubuntu USN-1163-1 2011-07-05
Pardus 2011-100 2011-08-03
Gentoo 201206-01 2012-06-02

Comments (none posted)

dokuwiki: cross-site scripting

Package(s):dokuwiki CVE #(s):CVE-2011-2510
Created:July 7, 2011 Updated:October 10, 2011
Description:

From the Red Hat Bugzilla entry:

It was found that DokuWiki's RSS embedding mechanism did not properly escape user-provided links. An attacker could use this flaw to conduct cross-site scripting (XSS) attacks, potentially leading to arbitrary JavaScript code execution.

Alerts:
Debian DSA-2320-1 2011-10-08
Fedora FEDORA-2011-8831 2011-06-28
Fedora FEDORA-2011-8816 2011-06-28
Gentoo 201301-07 2013-01-09

Comments (none posted)

feh: arbitrary file overwrite

Package(s):feh CVE #(s):CVE-2011-0702
Created:July 5, 2011 Updated:October 14, 2011
Description: From the Red Hat bugzilla:

A Debian bug report indicated that feh is vulnerable to an arbitrary file overwrite flaw. If a user could guess the PID of the feh process and create a symlink in /tmp, they could cause the overwrite of any file that the user running feh has write access to via wget overwriting the file.

Alerts:
Gentoo 201110-08 2011-10-13
Fedora FEDORA-2011-8747 2011-06-26
Fedora FEDORA-2011-8750 2011-06-26

Comments (none posted)

krb5-appl: privilege escalation

Package(s):krb5-appl CVE #(s):CVE-2011-1526
Created:July 5, 2011 Updated:March 22, 2012
Description: From the Red Hat advisory:

It was found that gssftp, a Kerberos-aware FTP server, did not properly drop privileges. A remote FTP user could use this flaw to gain unauthorized read or write access to files that are owned by the root group.

Alerts:
openSUSE openSUSE-SU-2011:1169-1 2011-10-24
Debian DSA-2283-1 2011-07-25
Mandriva MDVSA-2011:117 2011-07-22
Fedora FEDORA-2011-9109 2011-07-06
Fedora FEDORA-2011-9080 2011-07-06
Scientific Linux SL-krb5-20110705 2011-07-05
Red Hat RHSA-2011:0920-01 2011-07-05
openSUSE openSUSE-SU-2012:0019-1 2012-01-05
SUSE SUSE-SU-2012:0010-1 2012-01-05
SUSE SUSE-SU-2012:0042-1 2012-01-05
Gentoo 201201-14 2012-01-23
Red Hat RHSA-2012:0306-03 2012-02-21
Oracle ELSA-2012-0306 2012-03-07
Scientific Linux SL-krb5-20120321 2012-03-21

Comments (none posted)

lftp: man-in-the-middle vulnerability

Package(s):lftp CVE #(s):
Created:July 7, 2011 Updated:July 7, 2011
Description:

From the Pardus advisory:

lftp up to and including version 4.1.3 has an option "ssl:verify-certificate" which unfortunatly defaults to "no". Ie no certificate checks. Moreover, when compiled with openssl rather than gnutls lftp does not turn off SSLv2 (bad for openssl pre 1.0) and lacks code to actually verify the hostname. Ie it's prone to MITM.

Alerts:
Pardus 2011-91 2011-07-06

Comments (none posted)

libvoikko: denial of service

Package(s):libvoikko CVE #(s):
Created:July 1, 2011 Updated:July 7, 2011
Description: From the Fedora advisory:

Backport a security fix from version 3.2.1: Fix handling of embedded null characters in input strings entered through the Python interface. The bug could be used to cause denial of service conditions and possibly other problems. Users of these interfaces are recommended to upgrade to this release. Applications that use the native C++ library directly (this includes all well known desktop applications) are not affected by this bug and no changes to the native library have been made in this release.

Alerts:
Fedora FEDORA-2011-8232 2011-06-14
Fedora FEDORA-2011-8227 2011-06-14

Comments (none posted)

NetworkManager: privilege escalation

Package(s):NetworkManager CVE #(s):CVE-2011-2176
Created:July 7, 2011 Updated:November 23, 2011
Description:

From the Red Hat Bugzilla entry:

It was found that NetworkManager, a network devices and connections manager, did not properly enforce the PolicyKit 'auth_admin' action element settings (did not require authentication by an administrative user), when the 'auth_admin' element was specified in org.freedesktop.network-manager-settings.system.wifi.share.open (connection sharing via an open WiFi network) action. A local attacker could use this flaw to setup an unsecure (passwordless) Ad-Hoc wireless network.

Alerts:
openSUSE openSUSE-SU-2011:1273-1 2011-11-23
Mandriva MDVSA-2011:171 2011-11-11
Fedora FEDORA-2011-8612 2011-06-24
Scientific Linux SL-Netw-20110712 2011-07-12
Red Hat RHSA-2011:0930-01 2011-07-12
Fedora FEDORA-2011-9005 2011-07-03

Comments (none posted)

nfs-utils: authentication bypass

Package(s):nfs-utils CVE #(s):CVE-2011-2500
Created:July 7, 2011 Updated:July 19, 2011
Description:

From the Red Hat Bugzilla entry:

A security flaw was found in the way nfs-utils performed authentication of an incoming request, when an IP based authentication mechanism was used and certain file systems were exported to either to a netgroup or a wildcard (e.g. *.my.domain), and some file systems (either the same or different to the first set) were exported to specific hosts, IP addresses, or a subnet. A remote attacker, able to create global DNS entries could use this flaw to access above listed, exported file systems.

Alerts:
Scientific Linux SL-nfs--20111206 2011-12-06
Red Hat RHSA-2011:1534-03 2011-12-06
openSUSE openSUSE-SU-2011:0747-1 2011-07-19
Fedora FEDORA-2011-8934 2011-07-01

Comments (none posted)

OpenSSH: private key disclosure

Package(s):openssh CVE #(s):
Created:July 7, 2011 Updated:July 8, 2011
Description:

From the OpenSSH advisory:

ssh-keysign is a setuid helper program that is used to mediate access to the host's private host keys during host-based authentication. It would use its elevated privilege to open the keys and then immediately drop privileges to complete its cryptographic signing operations.

After privilege was dropped, ssh-keysign would ensure that the OpenSSL random number generator that it depends upon was adequately prepared. On configurations that lacked a built-in source of entropy in OpenSSL, ssh-keysign would execute the ssh-rand-helper program to attempt to retrieve some from the system environment.

However, the file descriptors to the host private key files were not closed prior to executing ssh-rand-helper. Since this process was "born unprivileged" and inherited the sensitive file descriptors, there was no protection against an attacker using ptrace(2) to attach to it and instructing it to read out the private keys.

Alerts:
Pardus 2011-89 2011-07-06

Comments (1 posted)

packagekit: incorrect package signature check

Package(s):PackageKit CVE #(s):CVE-2011-2515
Created:July 5, 2011 Updated:July 7, 2011
Description: From the Red Hat bugzilla:

the basic problem here is that yum changed what PackageKit was relying on, and the end result is that a user can install an unsigned package without a GPG check, but be told by PackageKit that it is in fact signed (and trusted). It still requires a user to download said unsigned package manually (or from a rogue repo that is already setup) and also requires authentication to install the package.

Alerts:
Fedora FEDORA-2011-8943 2011-07-01

Comments (none posted)

php: arbitrary file creation/overwrite

Package(s):php5 CVE #(s):CVE-2011-2202
Created:June 30, 2011 Updated:April 13, 2012
Description:

From the Debian advisory:

CVE-2011-2202: Path names in form based file uploads (RFC 1867) were incorrectly validated.

Alerts:
Oracle ELSA-2011-1423 2011-11-03
Oracle ELSA-2011-1423 2011-11-03
Scientific Linux SL-NotF-20111102 2011-11-02
Mandriva MDVSA-2011:165 2011-11-03
CentOS CESA-2011:1423 2011-11-03
Red Hat RHSA-2011:1423-01 2011-11-02
Ubuntu USN-1231-1 2011-10-18
openSUSE openSUSE-SU-2011:1138-1 2011-10-17
openSUSE openSUSE-SU-2011:1137-1 2011-10-17
Gentoo 201110-06 2011-10-10
Fedora FEDORA-2011-11537 2011-08-26
Fedora FEDORA-2011-11528 2011-08-26
Fedora FEDORA-2011-11537 2011-08-26
Fedora FEDORA-2011-11528 2011-08-26
Fedora FEDORA-2011-11537 2011-08-26
Fedora FEDORA-2011-11528 2011-08-26
Slackware SSA:2011-237-01 2011-08-25
Debian DSA-2266-1 2011-06-29
Red Hat RHSA-2012:0033-01 2012-01-18
CentOS CESA-2012:0033 2012-01-18
Oracle ELSA-2012-0033 2012-01-18
Scientific Linux SL-php-20120119 2012-01-19
Red Hat RHSA-2012:0071-01 2012-01-30
CentOS CESA-2012:0071 2012-01-30
Oracle ELSA-2012-0071 2012-01-31
Scientific Linux SL-php-20120130 2012-01-30
SUSE SUSE-SU-2012:0496-1 2012-04-12
Mandriva MDVSA-2012:071 2012-05-10
Oracle ELSA-2012-1046 2012-06-30

Comments (none posted)

qemu-kvm: arbitrary code execution

Package(s):qemu-kvm CVE #(s):CVE-2011-2512
Created:July 5, 2011 Updated:July 19, 2011
Description: From the Debian advisory:

It was discovered that incorrect sanitising of virtio queue commands in KVM, a solution for full virtualization on x86 hardware, could lead to denial of service of the execution of arbitrary code.

Alerts:
SUSE SUSE-SU-2011:0806-1 2011-07-19
openSUSE openSUSE-SU-2011:0803-1 2011-07-19
Ubuntu USN-1165-1 2011-07-06
Scientific Linux SL-qemu-20110705 2011-07-05
Red Hat RHSA-2011:0919-01 2011-07-05
Debian DSA-2270-1 2011-07-01
Gentoo 201210-04 2012-10-18

Comments (none posted)

qemu-kvm: privilege escalation

Package(s):qemu-kvm CVE #(s):CVE-2011-2212
Created:July 6, 2011 Updated:July 25, 2011
Description: The virtio subsystem in qemu-kvm suffers from a buffer overflow which can be exploited to crash the guest or execute arbitrary code.
Alerts:
Debian DSA-2282-1 2011-07-25
SUSE SUSE-SU-2011:0806-1 2011-07-19
openSUSE openSUSE-SU-2011:0803-1 2011-07-19
Ubuntu USN-1165-1 2011-07-06
Scientific Linux SL-qemu-20110705 2011-07-05
Red Hat RHSA-2011:0919-01 2011-07-05
Gentoo 201210-04 2012-10-18

Comments (none posted)

rubygem-activesupport: cross-site scripting

Package(s):rubygem-activesupport CVE #(s):CVE-2011-2197
Created:June 30, 2011 Updated:September 7, 2011
Description:

From the Red Hat Bugzilla entry:

An cross-site scripting (XSS) flaw was found in the way Ruby on Rails performed management of safe buffers (certain methods could append unsafe strings to buffers, already containing strings marked as safe without marking the resulting buffer as unsafe). A remote attack could use this flaw to conduct XSS attacks by tricking a local user into visiting a specially-crafted web page.

Alerts:
Fedora FEDORA-2011-8580 2011-06-24
Fedora FEDORA-2011-8494 2011-06-21

Comments (none posted)

syslog-ng: denial of service

Package(s):syslog-ng CVE #(s):CVE-2011-1951
Created:June 30, 2011 Updated:July 7, 2011
Description:

From the Red Hat Bugzilla entry:

A denial of service flaw was found in the way syslog-ng processed certain log patterns, when 'global' flag was specified and PCRE backend was used for matching. A remote attacker could use this flaw to cause excessive memory use by the syslog-ng process via specially-crafted pattern.

Alerts:
Fedora FEDORA-2011-8405 2011-06-21

Comments (none posted)

tftp: buffer overflow

Package(s):tftp CVE #(s):CVE-2011-2199
Created:July 5, 2011 Updated:July 10, 2012
Description: From the openSUSE advisory:

Malicious clients could overflow a buffer in tftpd by specifying a large value for the utimeout option.

Alerts:
openSUSE openSUSE-SU-2011:0734-1 2011-07-05
Gentoo 201206-12 2012-06-21
Mageia MGASA-2012-0147 2012-07-09

Comments (none posted)

weechat: man-in-the-middle attack

Package(s):weechat CVE #(s):CVE-2011-1428
Created:July 5, 2011 Updated:July 7, 2011
Description: From the CVE entry:

Wee Enhanced Environment for Chat (aka WeeChat) 0.3.4 and earlier does not properly verify that the server hostname matches the domain name of the subject of an X.509 certificate, which allows man-in-the-middle attackers to spoof an SSL chat server via an arbitrary certificate, related to incorrect use of the GnuTLS API.

Alerts:
Fedora FEDORA-2011-7839 2011-06-03
Fedora FEDORA-2011-7843 2011-06-03
Debian DSA-2598-1 2013-01-05

Comments (none posted)

wordpress: privilege escalation

Package(s):wordpress CVE #(s):
Created:July 7, 2011 Updated:July 12, 2011
Description:

From the WordPress advisory:

This release fixes an issue that could allow a malicious Editor-level user to gain further access to the site.

Alerts:
Fedora FEDORA-2011-8908 2011-06-30
Fedora FEDORA-2011-8877 2011-06-30

Comments (none posted)

xen: privilege escalation

Package(s):xen CVE #(s):CVE-2011-1898
Created:June 30, 2011 Updated:November 7, 2011
Description:

From the Xen advisory:

Intel VT-d chipsets without interrupt remapping do not prevent a guest which owns a PCI device from using DMA to generate MSI interrupts by writing to the interrupt injection registers. This can be exploited to inject traps and gain control of the host.

Alerts:
Scientific Linux SL-kern-20111129 2011-11-29
CentOS CESA-2011:1479 2011-11-30
Oracle ELSA-2011-1479 2011-11-30
Red Hat RHSA-2011:1479-01 2011-11-29
Debian DSA-2337-1 2011-11-06
SUSE SUSE-SU-2011:0942-1 2011-08-25
Scientific Linux SL-kern-20110823 2011-08-23
openSUSE openSUSE-SU-2011:0941-1 2011-08-25
Red Hat RHSA-2011:1189-01 2011-08-23
SUSE SUSE-SU-2011:0925-1 2011-08-19
Fedora FEDORA-2011-8421 2011-06-21
Fedora FEDORA-2011-8403 2011-06-21
Red Hat RHSA-2012:0358-01 2012-03-06

Comments (4 posted)

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