Debian: New python-dns package fixes regression
Posted by Benjamin D. Thomas   
Debian In DSA-1619-1, an update was announced for DNS response spoofing vulnerabilities in python-dns. The fix introduced a regression in the library breaking the resolution of UTF-8 encoded record names. An updated release is available which corrects this problem. For reference, the original advisory text follows.
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Debian Security Advisory DSA-1619-2                  security@debian.org
http://www.debian.org/security/                           Devin Carraway
September 22, 2008                    http://www.debian.org/security/faq
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Package        : python-dns
Vulnerability  : DNS response spoofing
Problem type   : remote
Debian-specific: no
CVE Id(s)      : CVE-2008-1447
Debian Bug     : 490217

In DSA-1619-1, an update was announced for DNS response spoofing
vulnerabilities in python-dns.  The fix introduced a regression in the
library breaking the resolution of UTF-8 encoded record names.  An
updated release is available which corrects this problem.  For
reference, the original advisory text follows.

Multiple weaknesses have been identified in PyDNS, a DNS client
implementation for the Python language.  Dan Kaminsky identified a
practical vector of DNS response spoofing and cache poisoning,
exploiting the limited entropy in a DNS transaction ID and lack of
UDP source port randomization in many DNS implementations.  Scott
Kitterman noted that python-dns is vulnerable to this predictability,
as it randomizes neither its transaction ID nor its source port.
Taken together, this lack of entropy leaves applications using
python-dns to perform DNS queries highly susceptible to response
forgery.

The Common Vulnerabilities and Exposures project identifies this
class of weakness as CVE-2008-1447.

For the stable distribution (etch), these problems have been fixed in
version 2.3.0-5.2+etch2.

We recommend that you upgrade your python-dns package.

Upgrade instructions
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wget url
        will fetch the file for you
dpkg -i file.deb
        will install the referenced file.

If you are using the apt-get package manager, use the line for
sources.list as given below:

apt-get update
        will update the internal database
apt-get upgrade
        will install corrected packages

You may use an automated update by adding the resources from the
footer to the proper configuration.


Debian GNU/Linux 4.0 alias etch
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Debian (stable)
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Stable updates are available for alpha, amd64, arm, hppa, i386, ia64, mips, mipsel, powerpc, s390 and sparc.

Source archives:

  http://security.debian.org/pool/updates/main/p/python-dns/python-dns_2.3.0-5.2+etch2.diff.gz
    Size/MD5 checksum:     3807 4c9dceefe0dfc4ee933f3c9298764153
  http://security.debian.org/pool/updates/main/p/python-dns/python-dns_2.3.0.orig.tar.gz
    Size/MD5 checksum:    21084 82d377c6a59181072b30b0da4e9835b8
  http://security.debian.org/pool/updates/main/p/python-dns/python-dns_2.3.0-5.2+etch2.dsc
    Size/MD5 checksum:      695 16b84a9d56bdd4baf5cdf1bf7e413521

Architecture independent packages:

  http://security.debian.org/pool/updates/main/p/python-dns/python-dns_2.3.0-5.2+etch2_all.deb
    Size/MD5 checksum:    22972 59775332c3bb11b1408c83cf25b8e253


  These files will probably be moved into the stable distribution on
  its next update.

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For apt-get: deb http://security.debian.org/ stable/updates main
For dpkg-ftp: ftp://security.debian.org/debian-security dists/stable/updates/main
Mailing list: debian-security-announce@lists.debian.org