Unauthenticated XSS in widely used GitLab CE/EE could affect many deployments and enable browser-based attacks.
CVE-2026-0752
Unauthenticated XSS in GitLab Mermaid sandbox UI.
Is CVE-2026-0752 being exploited?
Not confirmed. CVE-2026-0752 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 0.31% probability of exploitation in the next 30 days.
How severe is CVE-2026-0752?
CVE-2026-0752 is rated High with a CVSS score of 8.0. 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-2026-0752?
Yes. A fix has been recorded for CVE-2026-0752. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-0752 affect?
CVE-2026-0752 affects GitLab Community Edition (CE), GitLab Enterprise Edition (EE). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-0752?
Upgrade to patched releases (>=18.7.5, >=18.8.5, or >=18.9.1).
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated XSS via Mermaid sandbox; attacker injects JS executed in victims' browsers, risking data theft and session hijack.
Immediate action required
- affected>= 16.2 and < 18.7.5
- affected>= 18.8 and < 18.8.5
- affected>= 18.9 and < 18.9.1
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.