Vulnerability · Published Nov 5, 2026 · Assigned by GitHub_M

CVE-2026-102523MariaDB server: Authorization bypass via ALTER TABLE ... CONVERT ... PARTITION

High 8.0

In plain English

A high-severity security flaw in server from MariaDB. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities).

Severity (CVSS 3.1)8.0High

Exploit odds (30 days)0.6%top 53.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

MariaDB server is a community developed fork of MySQL server. From 10.11.1 until 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2, ALTER TABLE ... CONVERT ... PARTITION does not apply filename encoding to user-specified partition names before using them in filesystem path construction. An authenticated database user can use a partition name requiring filename escaping to make the conversion operate on table files the user is not authorized to access, allowing unauthorized table reads or modifications. This issue is fixed in versions 10.11.19, 11.4.13, 11.8.9, 12.3.3, and 13.0.2.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Ubuntu:24.04:LTS	mariadb	no fix listed	UBUNTU-CVE-2026-102523
Ubuntu:26.04:LTS	mariadb	no fix listed	UBUNTU-CVE-2026-102523
Ubuntu:26.10	mariadb	no fix listed	UBUNTU-CVE-2026-102523
Ubuntu:22.04:LTS	mariadb-10.6	no fix listed	UBUNTU-CVE-2026-102523

Affected products (as reported)

Vendor	Product	Versions
MariaDB	server	>= 10.11.1, < 10.11.19>= 11.4.1, < 11.4.13>= 11.8.1, < 11.8.9>= 12.3.1, < 12.3.3>= 13.0.1, < 13.0.2

Weakness: CWE-73 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

References

https://github.com/MariaDB/server/security/advisories/GHSA-h4vr-wpff-jfx4 x_refsource_CONFIRM
https://github.com/MariaDB/server/commit/98437c30ae52ed709f266e5f8095d779261a5879 x_refsource_MISC
https://github.com/MariaDB/server/releases/tag/mariadb-10.11.19 x_refsource_MISC
https://github.com/MariaDB/server/releases/tag/mariadb-11.4.13 x_refsource_MISC
https://github.com/MariaDB/server/releases/tag/mariadb-11.8.9 x_refsource_MISC
https://github.com/MariaDB/server/releases/tag/mariadb-12.3.3 x_refsource_MISC
https://github.com/MariaDB/server/releases/tag/mariadb-13.0.2 x_refsource_MISC
https://jira.mariadb.org/browse/MDEV-40413 x_refsource_MISC