8.4
HIGH CVSS 4.0
CVE-2026-76833
@cgauge/yaml npm Package Arbitrary Code Execution via eval() YAML Tag
Description

@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.

INFO

Published Date :

Aug. 20, 2026, 2:18 p.m.

Last Modified :

Aug. 20, 2026, 3:18 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-76833 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update the @cgauge/yaml package to a version that addresses the arbitrary code execution vulnerability.
  • Update to the latest safe version of @cgauge/yaml.
  • Avoid parsing untrusted YAML input.
  • Sanitize user-supplied YAML input.
  • Use a secure YAML parser.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-76833 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-76833 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-76833 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-76833 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 20, 2026

    Action Type Old Value New Value
    Added Reference https://gist.github.com/arjunjaincs/35da3a80b4b16f324f194acec18489ba
    Added SSVC {'id': 'CVE-2026-76833', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-20T14:28:52.031389Z'}
  • New CVE Received by [email protected]

    Aug. 20, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'cgauge', 'product': '@cgauge/yaml', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '0.27.0'}], 'packageURL': 'pkg:cargo/dua-cli', 'defaultStatus': 'affected'}]
    Added Description @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.
    Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
    Added CWE CWE-95
    Added Reference https://gist.github.com/arjunjaincs/35da3a80b4b16f324f194acec18489ba
    Added Reference https://github.com/cgauge/packages
    Added Reference https://www.vulncheck.com/advisories/cgauge-yaml-npm-package-arbitrary-code-execution-via-eval-yaml-tag
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.