CVE-2026-76833

@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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/arjunjaincs/35da3a80b4b16f324f194acec18489ba
https://github.com/cgauge/packages
https://www.vulncheck.com/advisories/cgauge-yaml-npm-package-arbitrary-code-execution-via-eval-yaml-tag
https://gist.github.com/arjunjaincs/35da3a80b4b16f324f194acec18489ba

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-20 14:18

Updated : 2026-08-20 15:18

NVD link : CVE-2026-76833

Mitre link : CVE-2026-76833

CVE.ORG link : CVE-2026-76833

JSON object : View

Products Affected

No product.

CWE

CWE-95

Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')

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