Copyright © 2012 Red Hat, Inc. All rights reserved. Important 2026-09-15T00:00:00 leapp-repository: leapp-upgrade-el9toel10: leapp-upgrade-el9toel10: scan_mysql runs mysqld --validate-config as root and can load mysql-writable plugins 7.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H CWE-250

A privilege escalation flaw was found in the scan_mysql actor of leapp-upgrade-el9toel10 (provided by leapp-repository). During RHEL 9 to RHEL 10 upgrades, the actor runs: mysqld --validate-config --log-error-verbosity=2 directly as root in the Leapp actor context, bypassing the packaged MySQL systemd unit that normally starts the daemon as User=mysql. A process compromised as the mysql OS identity can write a version-2 persisted configuration (mysqld-auto.cnf) and a malicious shared object into /var/lib/mysql (a directory owned by mysql). That persisted map can set plugin_dir to /var/lib/mysql and early_plugin_load (or related loader options such as plugin_load / plugin_load_add) so MySQL loads the attacker-controlled object during configuration validation. Plugin loading can reach dlopen() before MySQL’s runtime-user check and before plugin-symbol validation. When an administrator subsequently runs the documented Leapp preupgrade or upgrade workflow, attacker-controlled code can execute as UID 0 with a full capability set in an unconfined SELinux domain (unconfined_t). The attack does not require write access to the default system plugin path under /usr; redirecting plugin_dir via mysql-owned persisted state is sufficient. Ordinary SQL privileges alone (including highly privileged SQL accounts) are not a sufficient startpoint — OS-level execution as the mysql service identity is required, plus later administrator invocation of Leapp.

A privilege escalation flaw was found in the scan_mysql actor of leapp-upgrade-el9toel10 (provided by leapp-repository). During RHEL 9 to RHEL 10 upgrades, the actor runs: mysqld --validate-config --log-error-verbosity=2 directly as root in the Leapp actor context, bypassing the packaged MySQL systemd unit that normally starts the daemon as User=mysql. A process compromised as the mysql OS identity can write a version-2 persisted configuration (mysqld-auto.cnf) and a malicious shared object into /var/lib/mysql (a directory owned by mysql). That persisted map can set plugin_dir to /var/lib/mysql and early_plugin_load (or related loader options such as plugin_load / plugin_load_add) so MySQL loads the attacker-controlled object during configuration validation. Plugin loading can reach dlopen() before MySQL’s runtime-user check and before plugin-symbol validation. When an administrator subsequently runs the documented Leapp preupgrade or upgrade workflow, attacker-controlled code can execute as UID 0 with a full capability set in an unconfined SELinux domain (unconfined_t). The attack does not require write access to the default system plugin path under /usr; redirecting plugin_dir via mysql-owned persisted state is sufficient. Ordinary SQL privileges alone (including highly privileged SQL accounts) are not a sufficient startpoint — OS-level execution as the mysql service identity is required, plus later administrator invocation of Leapp.

This is an Important privilege escalation flaw in the Leapp upgrade process from RHEL 9 to RHEL 10. An attacker with prior OS-level code execution as the `mysql` service user can leverage this during a Leapp preupgrade or upgrade to execute arbitrary code as root. This occurs because the `scan_mysql` actor invokes `mysqld --validate-config` as root, allowing it to load malicious plugins from a MySQL-owned directory. Red Hat would like to thank Christopher Lusk (North Echo Security Research) for reporting this issue. Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Red Hat Enterprise Linux 9 2026-09-15T00:00:00Z RHSA-2026:67608 leapp-repository-0:0.24.0-1.el9_8.1 Red Hat Enterprise Linux 9.6 Extended Update Support 2026-09-15T00:00:00Z RHSA-2026:67609 leapp-repository-0:0.22.0-1.el9_6.2 Red Hat Enterprise Linux 8 Not affected leapp-repository Red Hat OpenStack Platform 17.1 Not affected leapp-repository-openstack https://www.cve.org/CVERecord?id=CVE-2026-75092 https://nvd.nist.gov/vuln/detail/CVE-2026-75092 https://github.com/oamg/leapp-repository https://github.com/oamg/leapp-repository/commit/3e4cafffc8de1600a66519b326a407f37b665356 https://github.com/oamg/leapp-repository/pull/1343