PowerDNS Recursor before 3.1.6 does not always use the strongest random number generator for source port selection, which makes it easier for remote attack vectors to conduct DNS cache poisoning. NOTE: this is related to incomplete integration of security improvements associated with addressing CVE-2008-1637.

According to its self-reported version number, the version of PowerDNS Recursor listening on the remote host is version 3.x prior to 3.1.6.
It is, therefore, affected by a cache poisoning vulnerability due to insufficient randomness to calculate TRXID values and UDP source port numbers. A remote attacker can exploit this poison the DNS cache. This vulnerability was originally fixed in version 3.1.5, but a more secure method was implemented in version 3.1.6.

Note that Nessus has not attempted to exploit this issue but has instead relied only on the application's self-reported version number.
Also, Nessus has not checked for the presence of the patch or the workaround.

- Fri Jul 25 2008 Ruben Kerkhof <ruben at     rubenkerkhof.com> - 3.1.7-2

    - Exclude ppc and ppc64 for now, the build fails       randomly

    - Fri Jul 25 2008 Ruben Kerkhof <ruben at       rubenkerkhof.com> - 3.1.7-1

    - Upstream released new version, now with Lua support

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The remote host is affected by the vulnerability described in GLSA-200804-22 (PowerDNS Recursor: DNS Cache Poisoning)

    Amit Klein of Trusteer reported that insufficient randomness is used to     calculate the TRXID values and the UDP source port numbers     (CVE-2008-1637). Thomas Biege of SUSE pointed out that a prior fix to     resolve this issue was incomplete, as it did not always enable the     stronger random number generator for source port selection     (CVE-2008-3217).
  Impact :

    A remote attacker could send malicious answers to insert arbitrary DNS     data into the cache. These attacks would in turn help an attacker to     perform man-in-the-middle and site impersonation attacks.
  Workaround :

    There is no known workaround at this time.

Amit Klein discovered that pdns-recursor, a caching DNS resolver, uses a weak random number generator to create DNS transaction IDs and UDP source port numbers. As a result, cache poisoning attacks were simplified. (CVE-2008-1637 and CVE-2008-3217 )

ID	Name	Product	Family	Severity
34044	PowerDNS Recursor 3.x < 3.1.6 DNS Predictable Transaction ID (TRXID) Cache Poisoning	Nessus	DNS	medium
33770	Fedora 9 : pdns-recursor-3.1.7-2.fc9 (2008-6893)	Nessus	Fedora Local Security Checks	medium
32015	GLSA-200804-22 : PowerDNS Recursor: DNS Cache Poisoning	Nessus	Gentoo Local Security Checks	medium
31950	Debian DSA-1544-2 : pdns-recursor - design flaw	Nessus	Debian Local Security Checks	medium

Detections

Analytics

CVE-2008-3217

high

Tenable Plugins

medium

medium

medium

medium