stunnel: Security bypass — GLSA 200808-08

stunnel does not properly prevent the authentication of a revoked certificate which would be published by OCSP.

Affected Packages

net-misc/stunnel on all architectures
Affected versions < 4.24
Unaffected versions >= 4.24
< 4

Background

The stunnel program is designed to work as an SSL encryption wrapper between a remote client and a local or remote server. OCSP (Online Certificate Status Protocol), as described in RFC 2560, is an internet protocol used for obtaining the revocation status of an X.509 digital certificate.

Description

An unspecified bug in the OCSP search functionality of stunnel has been discovered.

Impact

A remote attacker can use a revoked certificate that would be successfully authenticated by stunnel. This issue only concerns the users who have enabled the OCSP validation in stunnel.

Workaround

There is no known workaround at this time.

Resolution

All stunnel users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-misc/stunnel-4.24"

References

Release Date
August 08, 2008

Latest Revision
August 09, 2009: 02

Severity
low

Exploitable
remote

Bugzilla entries