High 7.2Published Apr 28, 2026

CVE-2026-42615GCHQ CyberChef before 11.0.0 allows XSS via Show Base64 offsets, as demonstrated by the /#recipe=Show_Base64_offsets('%3Cscript substring.

Updated under an hour ago (Oct 27, 2026, 10:10 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for GCHQ CyberChef

Exploited in the last 30 days

GCHQ CyberChef before 11.0.0 allows XSS via Show Base64 offsets, as demonstrated by the /#recipe=Show_Base64_offsets('%3Cscript substring.

CVSS: 7.2 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Weakness (CWE): CWE-79
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mitre
NVD analysis: Awaiting Analysis
Record last updated: Apr 29, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

GCHQ CyberChef gchq:cyberchef (from the name)	before 11.0.0	CNA record

References

References

https://github.com/gchq/CyberChef/issues/2344
https://github.com/gchq/CyberChef/commit/9641ae07f92e9af50f10e978385465b2f4a36c4d
https://github.com/gchq/CyberChef/compare/v10.24.0...v11.0.0
https://github.com/gchq/CyberChef/pull/2346

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.