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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-50159 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 5.3 MEDIUM
Vector:  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

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/mermaid-js/mermaid/commit/12d472c9ed43f94814b110da8d7a9ae6dd5266ed GitHub, Inc.
https://github.com/mermaid-js/mermaid/commit/7e83f1533318b307764d961906a73377266f4c5e GitHub, Inc.
https://github.com/mermaid-js/mermaid/pull/8022 GitHub, Inc.
https://github.com/mermaid-js/mermaid/releases/tag/[email protected] GitHub, Inc.
https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8 GitHub, Inc.
https://github.com/mermaid-js/mermaid/security/advisories/GHSA-6x64-9x62-f2gx GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-94 Improper Control of Generation of Code ('Code Injection') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-50159
NVD Published Date:
08/06/2026
NVD Last Modified:
08/06/2026
Source:
GitHub, Inc.