CVE-2026-57439
MediumCVSS 5.0Exploitation Probability (EPSS)
Low risk1th percentile - higher than 1% of all known CVEs
Summary
CyberChef before version 11.2.0 contains a prototype pollution vulnerability in the Series Chart operation, which accepts the __proto__ key when parsing user-supplied CSV. This can be chained with other operations like Parse UDP to inject malicious JavaScript into HTML output.
Risk Assessment
An attacker can inject malicious JavaScript code into CyberChef's output, potentially leading to data theft, session hijacking, or other attacks on users viewing the results.
Recommendation
Immediately update CyberChef to version 11.2.0 or later, which fixes this vulnerability.
Other vulnerabilities in CyberChef
See all- CVE-2026-72912Medium
CyberChef prior to 11.3.0 has a client-side CPU exhaustion vulnerability in the pretty-recipe parser in src/core/Utils.mjs when a malformed #recipe= URL fragment containing a large number of unmatched quote characters reaches Utils.parseRecipeConfig(). The function synchronously applies a complex global regular expression that may perform heavy backtracking before rejecting the input, causing the victim's browser tab to freeze during startup for seconds or longer. No code execution, data exfiltration, or privilege escalation occurs.
- CVE-2026-42615High
GCHQ CyberChef before version 11.0.0 contains an XSS vulnerability via the Show Base64 offsets function, allowing script injection.
Original NVD description (English source)
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.