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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-71438 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's configuration setters (mermaid.initialize, mermaidAPI.setConfig, and mermaidAPI.updateSiteConfig) merge caller-supplied configuration into Mermaid's internal config using the assignWithDepth deep-merge helper, which is vulnerable to prototype pollution. This is only exploitable if an application forwards untrusted data directly into one of these configuration entry points, which is outside their documented usage; diagram-supplied configuration (e.g. %%{init: {}}%% or YAML frontmatter) is not affected. 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 2.4 LOW
Vector:  CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:A/VC:N/VI:L/VA:L/SC:H/SI:H/SA:H

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/mermaid-js/mermaid/commit/2cd6dcf735533b323507e3e889ffdea870540b43 GitHub, Inc.
https://github.com/mermaid-js/mermaid/commit/c34b07a0815842327e70794d69b0c8c5a1e2a956 GitHub, Inc.
https://github.com/mermaid-js/mermaid/pull/8022 GitHub, Inc.
https://github.com/mermaid-js/mermaid/releases/tag/mermaid%4011.16.1 GitHub, Inc.
https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8 GitHub, Inc.
https://github.com/mermaid-js/mermaid/security/advisories/GHSA-c4c3-pg64-4m4v GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-1321 Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-71438
NVD Published Date:
08/06/2026
NVD Last Modified:
08/06/2026
Source:
GitHub, Inc.