CVE-2026-71437 (GCVE-0-2026-71437)

Vulnerability from cvelistv5 – Published: 2026-08-06 19:51 – Updated: 2026-08-07 17:37
VLAI
Title
Mermaid Architecture diagrams are vulnerable to prototype pollution
Summary
Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. From version 11.5.0 until 11.16.1, Mermaid Architecture Diagrams are vulnerable to prototype pollution when a diagram defines a group with an id of __proto__. Because the group id is used directly as an object property key without validation, an attacker who can supply diagram text can pollute Object.prototype, potentially affecting the behavior of the embedding application. This issue is fixed in version 11.16.1.
Severity
6.5 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:H/SI:H/SA:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-07 17:37 UTC
CWE
  • CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7974 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
mermaid-js mermaid Affected: >= 11.5.0, < 11.16.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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