Fail2ban: Denial of Service — GLSA 200702-05

A flaw in Fail2ban may allow remote attackers to deny access to arbitrary hosts.

Affected Packages

net-analyzer/fail2ban on all architectures
Affected versions < 0.6.2
Unaffected versions >= 0.6.2

Background

Fail2ban monitors log files for failed authentication attempts and can block hosts responsible for repeated attacks.

Description

A flaw in the method used to parse log entries allows remote, unauthenticated attackers to forge authentication attempts from other hosts.

Impact

A remote attacker can add arbitrary hosts to the block list, denying legitimate users access to a resource.

Workaround

There is no known workaround at this time.

Resolution

All Fail2ban users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-analyzer/fail2ban-0.6.2"

References

Release Date
February 16, 2007

Latest Revision
February 16, 2007: 01

Severity
normal

Exploitable
remote

Bugzilla entries