MariaDB: database privilege escalation via user / role name collision in the acl cache

Summary

MariaDB server is a community developed fork of MySQL server. From 10.6.1 until 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2, MariaDB's ACL cache could generate the same database-privilege cache key for role and localhost user names that matched because both used an empty IP component. An attacker with CREATE USER could create the colliding principal and, when the original principal's database privileges were cached, exercise privileges assigned to the other account. This issue is fixed in versions 10.6.28, 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2.

Timeline

1. Oct 9, 2026, 5:28 PM UTCCVE published
2. Oct 13, 2026, 8:14 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 13, 2026, 8:27 PM UTCRecord last updated

Affected versions

• MariaDB server

  From 10.6.1 · fixed in 10.6.28; From 10.11.1 · fixed in 10.11.19; From 11.4.1 · fixed in 11.4.13; From 11.8.1 · fixed in 11.8.9; From 12.3.1 · fixed in 12.3.3; From 13.0.1 · fixed in 13.0.2

• mariadbBitnami

  From 10.6.1 · fixed in 10.6.28; From 10.11.1 · fixed in 10.11.19; From 11.4.1 · fixed in 11.4.13; From 11.8.1 · fixed in 11.8.9; From 12.3.1 · fixed in 12.3.3; From 13.0.1 · fixed in 13.0.2

• mariadb-minBitnami

  From 10.6.1 · fixed in 10.6.28; From 10.11.1 · fixed in 10.11.19; From 11.4.1 · fixed in 11.4.13; From 11.8.1 · fixed in 11.8.9; From 12.3.1 · fixed in 12.3.3; From 13.0.1 · fixed in 13.0.2

• mysql-clientBitnami

  From 10.6.1 · fixed in 10.6.28; From 10.11.1 · fixed in 10.11.19; From 11.4.1 · fixed in 11.4.13; From 11.8.1 · fixed in 11.8.9; From 12.3.1 · fixed in 12.3.3; From 13.0.1 · fixed in 13.0.2

References 9