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.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.3): severity, escalated by confirmed exploitation. This CVE's 7.3 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.3 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it