MaraDNS: CNAME Denial of Service

2008-01-29T00:00:00
ID GLSA-200801-16
Type gentoo
Reporter Gentoo Foundation
Modified 2008-01-29T00:00:00

Description

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"