CVE-2019-15586 — A XSS exists in Gitlab CE/EE < 12

A XSS exists in Gitlab CE/EE < 12.1.10 in the Mermaid plugin.

01What is this vulnerability?

A XSS exists in Gitlab CE/EE < 12.1.10 in the Mermaid plugin.

02Affected products

Vendor	Product	Versions
GitLab	Gitlab CE/EE	before 12.1.10

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2020-01-28T02:14:59.000Z
• Last modified: 2024-08-05T00:49:13.628Z

09References

• hackerone.com — https://hackerone.com/reports/645043
• about.gitlab.com — https://about.gitlab.com/blog/2019/09/30/security-release-gitlab-12-dot-3-dot-2-…