Description
The TLS implementation in GnuTLS before 2.12.23, 3.0.x before 3.0.28, and 3.1.x before 3.1.7 does not properly consider timing side-channel attacks on a noncompliant MAC check operation during the processing of malformed CBC padding, which allows remote attackers to conduct distinguishing attacks and plaintext-recovery attacks via statistical analysis of timing data for crafted packets, a related issue to CVE-2013-0169.
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 14 | gnutls28 | 3.0.22-3 | — |
| Debian 13 | gnutls28 | 3.0.22-3 | — |
| Debian 12 | gnutls28 | 3.0.22-3 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | gnutls +3 | 2.8.5-10.el6_4.1 | RHSA-2013:0588 |
| RHEL 6 | rhev-hypervisor6 | 6.4-20130306.2.el6_4 | RHSA-2013:0636 |
| RHEL 5 | gnutls +2 | 1.4.1-10.el5_9.1 | RHSA-2013:0588 |
Advisories 2
- RHSA-2013:0636 Red Hat Security Advisory: rhev-hypervisor6 security and bug fix update Red Hat Security Advisories (RHSA) · Aug 5, 2026
- RHSA-2013:0588 Red Hat Security Advisory: gnutls security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
References
- 57260 third-party-advisory
- https://gitorious.org/gnutls/gnutls/commit/328ee22c1b3951e060c7124c7cb1cee592c59bc0
- http://www.gnutls.org/security.html#GNUTLS-SA-2013-1
- http://www.isg.rhul.ac.uk/tls/TLStiming.pdf
- 57274 third-party-advisory
- [oss-security] 20130205 Re: CVE request: TLS CBC padding timing flaw in various SSL / TLS implementations mailing-list
- SUSE-SU-2014:0320 vendor-advisory
- SUSE-SU-2014:0322 vendor-advisory
- http://nmav.gnutls.org/2013/02/time-is-money-for-cbc-ciphersuites.html
- USN-1752-1 vendor-advisory
- openSUSE-SU-2013:0807 vendor-advisory
- openSUSE-SU-2014:0346 vendor-advisory
- RHSA-2013:0588 vendor-advisory
- https://gitorious.org/gnutls/gnutls/commit/b8391806cd79095fe566f2401d8c7ad85a64b198