CVE-2026-41148: fallo de gravedad media en mermaid-js mermaid
Mermaid: Improper sanitization of `classDefs` in diagrams leads to CSS injection
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
13Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 5.3epss 0.3%
Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Versions 10.9.5 and prior, in addition to 11.0.0-alpha.1 through 11.12.0 are vulnerable to CSS injection through improper sanitization. The state diagram (and any other diagram type that routes user-controlled style strings through the createCssStyles parser) captures classDef values using an unrestricted regex that matches everything up to a newline. That value then flows unsanitized through addStyleClass() into createCssStyles() and is assigned to style.innerHTML, so a closing brace (}) in the value terminates the generated CSS selector and turns everything after it into a new CSS rule on the page. This enables page defacement, user tracking via url() callbacks, and DOM attribute exfiltration. This issue has been fixed in versions 10.9.6 and 11.15.0. If developers are unable to immediately upgrade, they can work around this issue by setting "securityLevel": "sandbox", which prevents the issue by rendering the mermaid diagram in a sandboxed <iframe>.
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
Productos afectados
mermaid-js · mermaidCVEs relacionadas — mermaid-js mermaid
En el mismo producto, de las más peligrosas a las menos.
CVE-2021-43861HIGHIncorrect sanitisation function leads to `XSS`EPSS 0.9%CVE-2022-31108MEDIUMArbitrary `CSS` injection into the generated graph affecting the container HTML in mermaid.jsEPSS 0.9%CVE-2025-54881MEDIUMMermaid improperly sanitizes of sequence diagram labels leading to XSSEPSS 0.8%CVE-2026-50159MEDIUMMermaid allows CSS injection applying to sibling elements of the diagramEPSS 0.6%CVE-2026-71436MEDIUMMermaid XY Charts are vulnerable to an infinite loop DoSEPSS 0.6%CVE-2026-71439MEDIUMMermaid radar diagrams are vulnerable to DoSEPSS 0.5%
Referencias
https://github.com/mermaid-js/mermaid/commit/8fead23c59166b7bab6a39eac81acebee2859102https://github.com/mermaid-js/mermaid/commit/e9b0f34d8d82a6260077764ee45e1d7d90957a0fhttps://github.com/mermaid-js/mermaid/releases/tag/mermaid%4011.15.0https://github.com/mermaid-js/mermaid/releases/tag/v10.9.6https://github.com/mermaid-js/mermaid/security/advisories/GHSA-xcj9-5m2h-648rhttps://mermaid.js.org/config/schema-docs/config.html#securitylevel