CVE-2026-41159
MEDIUM
5,3
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: passive
Confidentiality: N/A
Integrity: N/A
Availability: N/A
Description
AI Translation Available
Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.6 and 11.15.0, Mermaid's default configuration allows injecting CSS that applies outside of the Mermaid diagram via the fontFamily, themeCSS, and altFontFamily configuration options. The injected CSS exploits stylis's & (scope reference) handling. :not(&) escapes the #mermaid-xxx automatic scoping, applying styles to all page elements. Global at-rules (@font-face, @keyframes, @counter-style) are also injectable as stylis hoists them to top level. This allows page defacement and DOM attribute exfiltration via CSS :has() selectors. This vulnerability is fixed in 10.9.6 and 11.15.0.
94
Improper Control of Generation of Code ('Code Injection')
DraftCommon Consequences
Security Scopes Affected:
Access Control
Integrity
Confidentiality
Availability
Non-Repudiation
Potential Impacts:
Bypass Protection Mechanism
Gain Privileges Or Assume Identity
Execute Unauthorized Code Or Commands
Hide Activities
Applicable Platforms
Languages:
Interpreted
Technologies:
AI/ML
https://github.com/mermaid-js/mermaid/commit/64769738d5b59211e1decb471ffbaca8af…
https://github.com/mermaid-js/mermaid/releases/tag/[email protected]
https://github.com/mermaid-js/mermaid/releases/tag/v10.9.6
https://github.com/mermaid-js/mermaid/security/advisories/GHSA-87f9-hvmw-gh4p