Contao 4.6.0 before 5.3.54, 5.4.0-RC1 before 5.7.17, and 6.0.0-RC1 before 6.0.6 fails to invalidate existing user sessions when two-factor…
CVE-2026-128335
Contao 4.6.0 before 5.3.54, 5.4.0-RC1 before 5.7.17, and 6.0.0-RC1 before 6.0.6 fails to invalidate existing user sessions when two-factor authentication is enabled or disabled. Because Contao\User::isEqualTo() and serialized session data omit two-factor state, attackers already holding a session keep it after the owner changes 2FA settings.
Assessment
- CVSS
- 2.1 (v4.0)
- Severity
- Low
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 13 November 2026
- Last updated
- 13 November 2026
- Assigner
- VulnCheck
CVSS vectorCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
At the source
References
- https://github.com/contao/contao/security/advisories/GHSA-5mg3-mv6j-57wc
- https://github.com/contao/contao/commit/7e7c821ce6c41c02ae85b3d9f8eff5039de3fe1e
- https://github.com/contao/contao/commit/7618a5757347a30168139e74c7b326e3e296059d
- https://github.com/contao/contao/commit/843da308056402d94ae2dbb999959f9e2ce71fe1
- https://github.com/contao/contao/releases/tag/5.3.54
- https://github.com/contao/contao/releases/tag/5.7.17
- https://github.com/contao/contao/releases/tag/6.0.6
- https://github.com/contao/contao/blob/5.3.53/core-bundle/contao/library/Contao/User.php#L413-L446
- https://www.vulncheck.com/advisories/contao-before-5.3.54-5.7.17-and-6.0.6-session-invalidation-failure-on-2fa-change
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