CVE-2026-44171: MariaDB: path traversal in mbstream

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-12 · updated 2026-10-26
Weakness: CWE-22

Description

MariaDB server is a community developed fork of MySQL server. From versions 10.6.1 to before 10.6.26, 10.11.1 to before 10.11.17, 11.4.1 to before 11.4.11, 11.8.1 to before 11.8.7, and 12.3.1, mbstream did not check for /../ in the path when unpacking the archive. A proper backup can never contain such paths, but a specially crafted archive could have caused mbstream to create files outside of the target-dir path. This issue has been patched in versions 10.6.26, 10.11.17, 11.4.11, 11.8.7, and 12.3.2.

Affected products

MariaDB: from 10.6.1 before 10.6.26; from 10.11.1 before 10.11.17; from 11.4.1 before 11.4.11; from 11.8.1 before 11.8.7; 12.3.1 — fixed in 10.6.26, 10.11.17, 11.4.11, 11.8.7

How to fix

Upgrade to a fixed version: MariaDB 10.6.26, 10.11.17, 11.4.11, 11.8.7. Check the vendor advisory for mitigations.

References

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