CVE-2026-1090
Authenticated XSS in GitLab via markdown placeholders.
Is CVE-2026-1090 being exploited?
Not confirmed. CVE-2026-1090 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 0.23% probability of exploitation in the next 30 days.
How severe is CVE-2026-1090?
CVE-2026-1090 is rated High with a CVSS score of 8.7. 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-2026-1090?
Yes. A fix has been recorded for CVE-2026-1090. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-1090 affect?
CVE-2026-1090 affects GitLab CE/EE <=18.7.5 before 18.7.6, GitLab CE/EE 18.8.x before 18.8.6, GitLab CE/EE 18.9.x before 18.9.2. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-1090?
Upgrade to fixed GitLab versions (18.7.6+, 18.8.6+, 18.9.2+).
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated user can inject JavaScript via markdown_placeholders; in-browser code execution and potential data access.
Patch when possible
- affected>= 10.6 and < 18.7.6
- affected>= 18.8 and < 18.8.6
- affected>= 18.9 and < 18.9.2
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.