Description
verify.c in GnuTLS before 1.4.4, when using an RSA key with exponent 3, does not properly handle excess data in the digestAlgorithm.parameters field when generating a hash, which allows remote attackers to forge a PKCS #1 v1.5 signature that is signed by that RSA key and prevents GnuTLS from correctly verifying X.509 and other certificates that use PKCS, a variant of CVE-2006-4339.
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 3.1 | gnutls11 | 1.0.16-13.2sarge2 | DSA-1182-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 4 | gnutls +1 | 1.0.20-3.2.3 | RHSA-2006:0680 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | gnutls | 3.7.2-1.2 | openSUSE-SU-2024:10801-1 |
Advisories 3
- RHSA-2006:0680 Red Hat Security Advisory: gnutls security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1182-1 gnutls11 Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10801-1 gnutls-3.7.2-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- 25762 third-party-advisory
- 22992 third-party-advisory
- 21937 third-party-advisory
- 22049 third-party-advisory
- 1016844 vdb-entry
- ADV-2006-3899 vdb-entry
- 20027 vdb-entry
- SUSE-SR:2006:023 vendor-advisory
- MDKSA-2006:166 vendor-advisory
- RHSA-2006:0680 vendor-advisory
- http://www.gnu.org/software/gnutls/security.html
- oval:org.mitre.oval:def:9937 vdb-entry signature
- 102970 vendor-advisory
- ADV-2006-3635 vdb-entry
- 21942 third-party-advisory
- [gnutls-dev] 20060908 Variant of Bleichenbacher's crypto 06 rump session attack mailing-list
- 22080 third-party-advisory
- GLSA-200609-15 vendor-advisory
- SUSE-SA:2007:010 vendor-advisory
- DSA-1182 vendor-advisory
- http://support.avaya.com/elmodocs2/security/ASA-2006-250.htm
- gnutls-rsakey-security-bypass(28953) vdb-entry
- 102648 vendor-advisory
- 21973 third-party-advisory
- 22226 third-party-advisory
- 22084 third-party-advisory
- [gnutls-dev] 20060912 Re: Variant of Bleichenbacher's crypto 06 rump session attack mailing-list
- USN-348-1 vendor-advisory
- ADV-2007-2289 vdb-entry
- 22097 third-party-advisory