CVE-2026-50159
CVE-2026-50159 · Mermaid allows CSS injection applying to sibling elements of the diagram
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.8 and 11.16.1, Mermaid is vulnerable to CSS injection via sibling combinator selectors generated from diagram-supplied class or id names. An attacker who can supply diagram text can inject arbitrary CSS into the rendered page, potentially altering the appearance or behavior of unrelated page elements. This issue is fixed in versions 10.9.8 and 11.16.1.
CVSS 5.3 · Medium · EPSS 0.6% · Fix available
- Published
- Updated
Affected products and versions
mermaid
- Versions
- < 10.9.8: Affected
- >= 11.0.0-alpha.1, < 11.16.1: Affected
No fix published
node-mermaid Debian:14
- Versions
- 8.11.0+ds+~cs29.13.22-1
- 8.13.2+ds+~cs30.13.21-1
- 8.13.2+ds+~cs30.13.21-1.1
- 8.13.3+ds+~cs26.13.21-1
- 8.13.3+ds+~cs26.13.21-2
- 8.13.8+~cs10.4.16-1
- 8.14.0+ds1+~cs11.4.14-1
- 8.14.0+~cs11.4.14-1
- 8.7.0+ds+~cs27.17.17-1
- 8.7.0+ds+~cs27.17.17-2
- 8.7.0+ds+~cs27.17.17-2~bpo10+1
- 8.7.0+ds+~cs27.17.17-3
- 8.9.1+ds+~cs26.20.25-1
- 8.9.3+ds+~cs29.13.19-1
- 9.2.2+~2.0.0-1
- 9.2.2+~2.0.0-2
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
mermaid npm
- Affected ranges
- SEMVER: ≥ 11.0.0-alpha.1, < 11.16.1
Update to 11.16.1
mermaid npm
- Affected ranges
- SEMVER: < 10.9.8
Update to 10.9.8
node-mermaid Ubuntu:22.04:LTS
- Versions
- 8.7.0+ds+~cs27.17.17-3
- 8.13.3+ds+~cs26.13.21-1
- 8.13.3+ds+~cs26.13.21-2
- 8.13.8+~cs10.4.16-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
node-mermaid Ubuntu:26.10
- Versions
- 9.2.2+~2.0.0-1
- 9.2.2+~2.0.0-2
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
Original sources
- https://github.com/mermaid-js/mermaid/security/advisories/GHSA-6x64-9x62-f2gx
- https://github.com/mermaid-js/mermaid/pull/8022
- https://github.com/mermaid-js/mermaid/commit/12d472c9ed43f94814b110da8d7a9ae6dd5266ed
- https://github.com/mermaid-js/mermaid/commit/7e83f1533318b307764d961906a73377266f4c5e
- https://github.com/mermaid-js/mermaid/releases/tag/[email protected]
- https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8
- https://nvd.nist.gov/vuln/detail/CVE-2026-50159