Arch Linux alert ASA-201611-3 (bind)

From:
    	     
 
Santiago Torres-Arias <santiago@archlinux.org> 
To:
    	     
 
Archlinux security <arch-security@archlinux.org> 
Subject:
    	     
 
[arch-security] [ASA-201611-3] bind: denial of service 
Date:
    	     
 
Tue, 1 Nov 2016 16:53:01 -0400
Message-ID:
    	     
 
<20161101205300.jj65tw35rmetv2h5@riseup.net>
Arch Linux Security Advisory ASA-201611-3
=========================================

Severity: High
Date    : 2016-11-01
CVE-ID  : CVE-2016-8864
Package : bind
Type    : denial of service
Remote  : Yes
Link    : https://wiki.archlinux.org/index.php/CVE

Summary
=======

The package bind before version 9.11.0.P1-1 is vulnerable to denial of
service.

Resolution
==========

Upgrade to 9.11.0.P1-1.

# pacman -Syu "bind>=9.11.0.P1-1"

The problem has been fixed upstream in version 9.11.0.P1.

Workaround
==========

None.

Description
===========

A defect in BIND's handling of responses containing a DNAME answer can
cause a resolver to exit after encountering an assertion failure in
db.c or resolver.c

During processing of a recursive response that contains a DNAME record
in the answer section, BIND can stop execution after encountering an
assertion error in resolver.c (error message: "INSIST((valoptions &
0x0002U) != 0) failed") or db.c (error message: "REQUIRE(targetp !=
((void *)0) && *targetp == ((void *)0)) failed").

A server encountering either of these error conditions will stop,
resulting in denial of service to clients.  The risk to authoritative
servers is minimal; recursive servers are chiefly at risk.

Impact
======

An attacker can send a crafted DNAME answer to crash the application.

References
==========

https://kb.isc.org/article/AA-01434/0
https://ftp.isc.org/isc/bind9/9.11.0-P1/RELEASE-NOTES-bin...
https://access.redhat.com/security/cve/CVE-2016-8864