High-severity code-eval isolation flaw in an enterprise database server (MarkLogic) that enables session compromise and unauthorized actions; affects widely deployed enterprise installs and warrants org-wide attention.
CVE-2026-9191
MarkLogic eval isolation flaw allows code execution and session compromise.
Is CVE-2026-9191 being exploited?
Not confirmed. CVE-2026-9191 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.21% probability of exploitation in the next 30 days.
How severe is CVE-2026-9191?
CVE-2026-9191 is rated Critical with a CVSS score of 9.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-9191?
Yes. A fix has been recorded for CVE-2026-9191. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-9191 affect?
CVE-2026-9191 affects Progress MarkLogic Server 12.x before 12.1.0, Progress MarkLogic Server 11.x before 11.3.7, REST/XDBC evaluation endpoints. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-9191?
Upgrade to 12.1.0 or 11.3.7, restrict/monitor eval endpoints, rotate creds/sessions
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated code execution via REST/XDBC can access HTTP request/response/session state, perform unauthorized actions, and hijack authenticated sessions.
Immediate action required
- affected>= 11.0.0 and < 11.3.7
- affected>= 12.0.0 and < 12.1.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.