Description
The authentication hook (mgs_hook_authz) in mod-gnutls 0.5.10 and earlier does not validate client certificates when "GnuTLSClientVerify require" is set, which allows remote attackers to spoof clients via a crafted certificate.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 7 | mod-gnutls | 0.5.10-1.1+deb7u1 | DSA-3177-1 |
| Debian 6.0 | mod-gnutls | 0.5.6-1+squeeze2 | DLA-170-1 |
Advisories 2
- DSA-3177-1 mod-gnutls - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-170-1 mod-gnutls - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- GLSA-201709-04 vendor-advisory
- DSA-3177 vendor-advisory
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578663
- http://issues.outoforder.cc/view.php?id=93