An updated squid package that fixes a denial of service issue is now available for Red Hat Enterprise Linux 4. This update has been rated as having moderate security impact by the Red Hat Security Response Team.
Squid is a full-featured Web proxy cache. A bug was found in the way Squid handles fully qualified domain name (FQDN) lookups. A malicious DNS server could crash Squid by sending a carefully crafted DNS response to an FQDN lookup. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-0446 to this issue. This erratum also includes two minor patches to the LDAP helpers. One corrects a slight malformation in ldap search requests (although all known LDAP servers accept the requests). The other adds documentation for the -v option to the ldap helpers. Users of Squid should upgrade to this updated package, which contains a backported patch, and is not vulnerable to this issue.