Vulnerability Description
CyberChef is a web app for encryption, encoding, compression, and data analysis. Prior to 11.2.0, the Series Chart operation accepts __proto__ as a key while parsing user-supplied CSV, allowing prototype pollution that can be chained with operations such as Parse UDP to inject malicious JavaScript into HTML output. This issue is fixed in version 11.2.0.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/gchq/CyberChef/commit/85db3be5d0096859b810f0e8d3e151d5dc9b948
- https://github.com/gchq/CyberChef/issues/2568
- https://github.com/gchq/CyberChef/pull/2569
- https://github.com/gchq/CyberChef/releases/tag/v11.2.0
- https://github.com/gchq/CyberChef/security/advisories/GHSA-fx6f-382r-j72c
- https://github.com/gchq/CyberChef/security/advisories/GHSA-fx6f-382r-j72c
FAQ
What is CVE-2026-57439?
CVE-2026-57439 is a vulnerability with a CVSS score of 5.0 (MEDIUM). CyberChef is a web app for encryption, encoding, compression, and data analysis. Prior to 11.2.0, the Series Chart operation accepts __proto__ as a key while parsing user-supplied CSV, allowing protot...
How severe is CVE-2026-57439?
CVE-2026-57439 has been rated MEDIUM with a CVSS base score of 5.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-57439?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.