Amit Klein of Trusteer discovered and documented weakness in a way PowerDNS Recursor generates DNS queries and transaction IDs used in DNS queries. This weakness can be used to predict transaction IDs used in a subsequent queries after observing certain amount of consequent previous queries, leading to a high possibility of performing a successful cache poisoning attack. PowerDNS Recursor 3.1.5 was released to address this issue. References: http://www.trusteer.com/docs/powerdnsrecursor.html http://doc.powerdns.com/powerdns-advisory-2008-01.html http://mailman.powerdns.com/pipermail/pdns-users/2008-March/005279.html http://www.securityfocus.com/archive/1/490330/30/
CVE-2008-1637 was assigned to this issue: PowerDNS Recursor before 3.1.5 uses insufficient randomness to calculate (1) TRXID values and (2) UDP source port numbers, which makes it easier for remote attackers to poison a DNS cache, related to (a) algorithmic deficiencies in rand and random functions in external libraries, (b) use of a 32-bit seed value, and (c) choice of the time of day as the sole seeding information.
pdns-recursor-3.1.5-1.fc8 has been submitted as an update for Fedora 8
pdns-recursor-3.1.5-1.fc7 has been submitted as an update for Fedora 7
pdns-recursor-3.1.5-1.fc7 has been pushed to the Fedora 7 stable repository. If problems still persist, please make note of it in this bug report.
pdns-recursor-3.1.5-1.fc8 has been pushed to the Fedora 8 stable repository. If problems still persist, please make note of it in this bug report.
This issue was addressed in: Fedora: https://admin.fedoraproject.org/updates/F7/FEDORA-2008-3010 https://admin.fedoraproject.org/updates/F8/FEDORA-2008-3036