Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') Affecting node-mermaid package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DEBIAN11-NODEMERMAID-18582776
- published7 Aug 2026
- disclosed6 Aug 2026
Introduced: 6 Aug 2026
CVE-2026-71438 (opens in a new tab)How to fix?
There is no fixed version for Debian:11 node-mermaid.
NVD Description
Note: Versions mentioned in the description apply only to the upstream node-mermaid package and not the node-mermaid package as distributed by Debian.
See How to fix? for Debian:11 relevant fixed versions and status.
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.
References
- https://security-tracker.debian.org/tracker/CVE-2026-71438
- https://github.com/mermaid-js/mermaid/commit/2cd6dcf735533b323507e3e889ffdea870540b43
- https://github.com/mermaid-js/mermaid/commit/c34b07a0815842327e70794d69b0c8c5a1e2a956
- https://github.com/mermaid-js/mermaid/pull/8022
- https://github.com/mermaid-js/mermaid/releases/tag/mermaid%4011.16.1
- https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8
- https://github.com/mermaid-js/mermaid/security/advisories/GHSA-c4c3-pg64-4m4v