CVE-2026-76833 (GCVE-0-2026-76833)

Vulnerability from cvelistv5 – Published: 2026-08-20 13:33 – Updated: 2026-08-20 14:29
VLAI
Title
@cgauge/yaml npm Package Arbitrary Code Execution via eval() YAML Tag
Summary
@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.
Severity
8.4 (High)
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
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 14:28 UTC
CWE
  • CWE-95 - Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6106 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
cgauge @cgauge/yaml Affected: 0 , ≤ 0.27.0 (custom)
guessed Create a notification for this product.
Date Public
2026-08-19 00:00
Credits
Arjun Jain
Show details on NVD website
To clipboard 

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