GLSA-200901-03 : pdnsd: Denial of Service and cache poisoning
Medium Nessus Plugin ID 35347
SynopsisThe remote Gentoo host is missing one or more security-related patches.
DescriptionThe remote host is affected by the vulnerability described in GLSA-200901-03 (pdnsd: Denial of Service and cache poisoning)
Two issues have been reported in pdnsd:
The p_exec_query() function in src/dns_query.c does not properly handle many entries in the answer section of a DNS reply, related to a 'dangling pointer bug' (CVE-2008-4194).
The default value for query_port_start was set to 0, disabling UDP source port randomization for outgoing queries (CVE-2008-1447).
An attacker could exploit the second weakness to poison the cache of pdnsd and thus spoof DNS traffic, which could e.g. lead to the redirection of web or mail traffic to malicious sites. The first issue can be exploited by enticing pdnsd to send a query to a malicious DNS server, or using the port randomization weakness, and might lead to a Denial of Service.
Port randomization can be enabled by setting the 'query_port_start' option to 1024 which would resolve the CVE-2008-1447 issue.
SolutionAll pdnsd users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose '>=net-dns/pdnsd-1.2.7'