Vulnerability · Published Oct 9, 2026 · Assigned by GitHub_M

CVE-2026-107851Contao: Improper access control in the table access voter

Medium 4.3

In plain English

A medium-severity incorrect authorization in contao from contao. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 91.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Contao is an Open Source CMS. From version 5.7.0 until 5.7.12, TableAccessVoter::hasAccessToModule() in core-bundle/src/Security/Voter/DataContainer/TableAccessVoter.php caches authorization decisions using only $tokenHash, a hash of the user's security token, and omits the table returned by getDataSource(). If one request first checks a table allowed to the user and then a different denied table, the voter can reuse the allowed result, while DefaultDataContainerVoter can convert an incorrect abstention into a grant. A low-privileged backend user can consequently read, create, update, or delete records in tables outside assigned module permissions, including tables containing member or newsletter-subscriber data. This issue is fixed in version 5.7.12.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	contao/core-bundle	5.7.12	GHSA-5974-gfqc-wrcm

Affected products (as reported)

Vendor	Product	Versions
contao	contao	>= 5.7.0, < 5.7.12

Weakness: CWE-524, CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

References

https://github.com/contao/contao/security/advisories/GHSA-5974-gfqc-wrcm x_refsource_CONFIRM
https://github.com/contao/contao/commit/9d6f582a4cc6a758ce11d1043fc9c0ba62c5f4c9 x_refsource_MISC
https://github.com/contao/contao/releases/tag/5.7.12 x_refsource_MISC