CVE-2026-76833 HIGH

CVE-2026-76833: @cgauge/yaml npm Package Arbitrary Code Execution via eval() YAML Tag

Vendor Cgauge
Product @cgauge/yaml
Weakness CWE-95 · Eval injection
Published August 20, 2026
Last update August 20, 2026

CVSS base score

8.4/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

@cgauge/yaml npm package contains an arbitrary code execution vulnerability that allows attackers to execute arbitrary JavaScript by embedding a custom !js YAML tag whose construct callback unconditionally calls eval() on attacker-supplied string values during document parsing. Any application parsing untrusted YAML input with this library exposes full Node.js runtime authority, including environment variable access, filesystem read/write, network access, and subprocess execution, with no safe-mode alternative or opt-out mechanism available.

Key dates

02Disclosure timeline

August 20, 2026 CVE published

Related vulnerabilities

04Related CVE