{"id":"CVE-2026-76833","aliases":["EUVD-2026-63350","GHSA-fqg3-vq72-r4q2"],"status":"published","title":"@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.","severity":{"version":"4.0","score":8.4,"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00219,"percentile":0.12503,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-95"],"published":"2026-08-20T13:33:14Z","modified":"2026-10-28T02:31:01Z","products":[{"vendor":"cgauge","product":"@cgauge/yaml"}],"references":[{"url":"https://github.com/cgauge/packages","tags":["product","package"]},{"url":"https://gist.github.com/arjunjaincs/35da3a80b4b16f324f194acec18489ba","tags":["technical-description","exploit","article"]},{"url":"https://www.vulncheck.com/advisories/cgauge-yaml-npm-package-arbitrary-code-execution-via-eval-yaml-tag","tags":["third-party-advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-76833","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-fqg3-vq72-r4q2"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76833.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-76833","title":"@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.","status":"published","published":"2026-08-20T13:33:14.674Z","modified":"2026-08-20T14:29:17.384Z","cvss":[{"version":"4.0","score":8.4,"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","level":"high","assessor":"cna"},{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-95"],"updated_at":"2026-11-02T13:46:21.568011Z"}],"euvd":[{"id":"EUVD-2026-63350","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.","status":"published","published":"2026-08-20T13:33:14Z","modified":"2026-08-20T14:29:17Z","cvss":[{"version":"4.0","score":8.4,"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","level":"high"}],"updated_at":"2026-11-02T18:01:40.451894Z"}],"ghsa":[{"id":"GHSA-fqg3-vq72-r4q2","title":"@cgauge/yaml npm package contains an arbitrary code execution vulnerability that allows attackers...","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.","status":"published","published":"2026-08-20T15:34:18Z","modified":"2026-08-20T15:34:26Z","cvss":[{"version":"4.0","score":8.4,"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/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","level":"high"},{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-95"],"updated_at":"2026-11-02T15:10:46.520021Z"}],"nvd":[{"id":"CVE-2026-76833","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.","status":"published","published":"2026-08-20T14:18:00.137Z","modified":"2026-10-18T20:10:00.11Z","cvss":[{"version":"4.0","score":8.4,"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/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","level":"high","assessor":"secondary"},{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-95"],"updated_at":"2026-11-02T14:12:40.302911Z"}],"osv":[{"id":"CVE-2026-76833","title":"@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.","status":"published","published":"2026-08-20T13:33:14.674Z","modified":"2026-10-28T02:31:01.140227536Z","cvss":[{"version":"4.0","score":8.4,"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","level":"high"}],"cwes":["CWE-95"],"updated_at":"2026-11-02T15:45:17.102988Z"}]}}