CVE-2026-57439

MEDIUM

CyberChef: Prototype pollution in Series Chart operation

Title source: cna
STIX 2.1

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.

References (5)

Core 5

Scores

CVSS v3 5.0
EPSS 0.0009
EPSS Percentile 0.7%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-1321 CWE-79
Status published
Products (1)
gchq/CyberChef < 11.2.0
Published Jul 08, 2026
Tracked Since Jul 08, 2026