SynopsisThe remote Debian host is missing a security-related update.
DescriptionSeveral cache-poisoning vulnerabilities have been discovered in BIND.
These vulnerabilities apply only if DNSSEC validation is enabled and trust anchors have been installed, which is not the default.
The Common Vulnerabilities and Exposures project identifies the following problems :
- CVE-2010-0097 BIND does not properly validate DNSSEC NSEC records, which allows remote attackers to add the Authenticated Data (AD) flag to a forged NXDOMAIN response for an existing domain.
- CVE-2010-0290 When processing crafted responses containing CNAME or DNAME records, BIND is subject to a DNS cache poisoning vulnerability, provided that DNSSEC validation is enabled and trust anchors have been installed.
- CVE-2010-0382 When processing certain responses containing out-of-bailiwick data, BIND is subject to a DNS cache poisoning vulnerability, provided that DNSSEC validation is enabled and trust anchors have been installed.
In addition, this update introduce a more conservative query behavior in the presence of repeated DNSSEC validation failures, addressing the 'roll over and die' phenomenon. The new version also supports the cryptographic algorithm used by the upcoming signed ICANN DNS root (RSASHA256 from RFC 5702), and the NSEC3 secure denial of existence algorithm used by some signed top-level domains.
This update is based on a new upstream version of BIND 9, 9.6-ESV-R1.
Because of the scope of changes, extra care is recommended when installing the update. Due to ABI changes, new Debian packages are included, and the update has to be installed using 'apt-get dist-upgrade' (or an equivalent aptitude command).
SolutionUpgrade the bind9 packages.
For the stable distribution (lenny), these problems have been fixed in version 1:9.6.ESV.R1+dfsg-0+lenny1.