CVE-2026-50159
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 4.0
- 5.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L - EPSS
- 0.6% chance of exploitation in the next 30 days; higher than 48% of CVEs (scores of 2026-10-25)
- CWE
- CWE-94
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-6x64-9x62-f2gx | npm | mermaid | >=11.0.0-alpha.1 <11.16.1 | 11.16.1 |
| GHSA-6x64-9x62-f2gx | npm | mermaid | <10.9.8 | 10.9.8 |
References
- https://github.com/mermaid-js/mermaid/commit/12d472c9ed43f94814b110da8d7a9ae6dd5266ed
- https://github.com/mermaid-js/mermaid/commit/7e83f1533318b307764d961906a73377266f4c5e
- https://github.com/mermaid-js/mermaid/pull/8022
- https://github.com/mermaid-js/mermaid/releases/tag/mermaid@11.16.1
- https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8