Medium 5.0Published Jul 8, 2026

CVE-2026-57439CyberChef: Prototype pollution in Series Chart operation

Updated under an hour ago (Oct 26, 2026, 7:00 PM ET)

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Every CVE for gchq CyberChef

Exploited in the last 30 days

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: 5.0 MEDIUM (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-79, CWE-1321
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Jul 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

gchq CyberChef gchq:cyberchef (from the name)	before 11.2.0	CNA record

References

References

https://github.com/gchq/CyberChef/security/advisories/GHSA-fx6f-382r-j72c	x-refsource-confirm
https://github.com/gchq/CyberChef/issues/2568	x-refsource-misc
https://github.com/gchq/CyberChef/pull/2569	x-refsource-misc
https://github.com/gchq/CyberChef/commit/85db3be5d0096859b810f0e8d3e151d5dc9b948f	x-refsource-misc
https://github.com/gchq/CyberChef/releases/tag/v11.2.0	x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.