[security - high] mariadb:10.11 security, bug fix, and enhancement update

MariaDB is a multi-user, multi-threaded SQL database server that is binary compatible with MySQL.

Security Fix(es):

* mariadb: MariaDB Server: Arbitrary code execution via wsrep_notify_cmd (CVE-2026-49261)

Bug Fix(es) and Enhancement(s):

* [RHEL8][tracker] Rebase Galera to 26.4.27 MariaDB:10.11 (JIRA:RHEL-145347)
* Rebase MariaDB 10.11 to 10.11.18 in RHEL8 (JIRA:RHEL-183088)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

CVE-2026-49261
MariaDB server is a community developed fork of MySQL server. Versions 10.6.1 through 10.6.26, 10.11.1 through 10.11.17, 11.4.1 through 11.4.11, 11.8.1 through 11.8.7, and 12.3.1 with `wsrep_notify_cmd` enabled would execute shell commands embedded in the name of the joiner node. This is fixed in 10.6.27, 10.11.18, 11.4.12, 11.8.8, and 12.3.2. As a workaround, anyone who cannot upgrade now should disable `wsrep_notify_cmd`.

Modularity name: "mariadb"
Stream name: "10.11"