CVE-2026-57439

CyberChef: Prototype pollution in Series Chart operation

MEDIUM
5
CVSS Score
Published: July 8, 2026 at 02:58 PM UTC
Updated: October 25, 2026 at 08:10 PM UTC
1 product affected across 1 vendorCyberChef

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Severity
MEDIUM5
Exploit prediction
EPSS 0.1%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 11.2.0
Affected range stops below 11.2.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5MEDIUMGitHub_M
Attack Vector
LOCAL
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-79CWE-1321

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