[ GLSA 200908-02 ] BIND: Denial of Service

[GLSA]

Gentoo Linux Security Advisory

Title: BIND: Denial of Service (GLSA 200908-02)
Severity: normal
Exploitable: remote
Date: August 01, 2009
Bug(s): #279508
ID: 200908-02

Synopsis


Dynamic Update packets can cause a Denial of Service in the BIND daemon.


Background


ISC BIND is the Internet Systems Consortium implementation of the
Domain Name System (DNS) protocol.


Affected Packages

Package: net-dns/bind
Vulnerable: < 9.4.3_p3
Unaffected: >= 9.4.3_p3
Architectures: All supported architectures


Description


Matthias Urlichs reported that the dns_db_findrdataset() function fails
when the prerequisite section of the dynamic update message contains a
record of type "ANY" and where at least one RRset for this FQDN exists
on the server.


Impact


A remote unauthenticated attacker could send a specially crafted
dynamic update message to the BIND daemon (named), leading to a Denial
of Service (daemon crash). This vulnerability affects all primary
(master) servers -- it is not limited to those that are configured to
allow dynamic updates.


Workaround


Configure a firewall that performs Deep Packet Inspection to prevent
nsupdate messages from reaching named. Alternatively, expose only
secondary (slave) servers to untrusted networks.


Resolution


All BIND users should upgrade to the latest version: