MaraDNS: CNAME Denial of service — GLSA 200801-16

MaraDNS is prone to a Denial of Service vulnerability impacting CNAME resolution.

Affected packages

net-dns/maradns on all architectures
Affected versions < 1.2.12.08
Unaffected versions >= 1.2.12.08

Background

MaraDNS is a package that implements the Domain Name Service (DNS) with resolver and caching ability.

Description

Michael Krieger reported that a specially crafted DNS could prevent an authoritative canonical name (CNAME) record from being resolved because of an "improper rotation of resource records".

Impact

A remote attacker could send specially crafted DNS packets to a vulnerable server, making it unable to resolve CNAME records.

Workaround

Add "max_ar_chain = 2" to the "marac" configuration file.

Resolution

All MaraDNS users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-dns/maradns-1.2.12.09"

References

Release date
January 29, 2008

Latest revision
January 29, 2008: 01

Severity
normal

Exploitable
remote

Bugzilla entries