CVE-2026-50159Mermaid allows CSS injection applying to sibling elements of the diagram
Updated under an hour ago ()
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No exploitation reported and no EPSS estimate yet.
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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 (v4.0, CNA)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
- Weakness (CWE)
- CWE-94
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- GitHub_M
- NVD analysis
- Awaiting Analysis
- Record last updated
- Aug 7, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
mermaid-js mermaid mermaid_js:mermaid (from the name) | before 10.9.8; from 11.0.0-alpha.1, < 11.16.1 | CNA record |
References
- https://github.com/mermaid-js/mermaid/security/advisories/GHSA-6x64-9x62-f2gxx-refsource-confirm
- https://github.com/mermaid-js/mermaid/pull/8022x-refsource-misc
- https://github.com/mermaid-js/mermaid/commit/12d472c9ed43f94814b110da8d7a9ae6dd5266edx-refsource-misc
- https://github.com/mermaid-js/mermaid/commit/7e83f1533318b307764d961906a73377266f4c5ex-refsource-misc
- https://github.com/mermaid-js/mermaid/releases/tag/mermaid@11.16.1x-refsource-misc
- https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8x-refsource-misc
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.