{"id":"CVE-2026-59870","revision":"8a8584eba0c64988ba34dc5266bac723","records":[{"revision":"8a8584eba0c64988ba34dc5266bac723","observedAt":"2026-10-25T14:19:22.811+00:00","statement":{"source":"nvd","id":"CVE-2026-59870","aliases":[],"title":"js-yaml is a JavaScript YAML parser and dumper. Prior to 3.15.1, 4.3.1, and 5.2.1, YAML11_SCHEMA support for the !!omap tag in src/tag/sequence/omap.ts uses omapTag.addItem() to perform a linear duplicate-key scan on every insertion, causin…","description":"js-yaml is a JavaScript YAML parser and dumper. Prior to 3.15.1, 4.3.1, and 5.2.1, YAML11_SCHEMA support for the !!omap tag in src/tag/sequence/omap.ts uses omapTag.addItem() to perform a linear duplicate-key scan on every insertion, causing O(n^2) CPU consumption when yaml.load() parses a crafted ordered-map document. In v3 and v4, !!omap is active and exploitable by default. v5 doesn't use !!omap by default, and the chances of activating it are very low.This issue is fixed in 3.15.1, 4.3.1, and 5.2.1.","state":0,"publishedAt":"2026-07-08T16:16:33.58+00:00","modifiedAt":"2026-10-06T16:17:08.49+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"},{"system":"CVSS 3.1 · nvd@nist.gov · Primary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/nodeca/js-yaml/commit/22a8071ef032117bc6249c330b240ac3aa2d3ded","https://github.com/nodeca/js-yaml/commit/39f3211a2f01b3c6982710cf21434ab7060acefe","https://github.com/nodeca/js-yaml/commit/c3cc4b0bb9ddb9af2dd9b61e0d56f5ce7983cd4a","https://github.com/nodeca/js-yaml/releases/tag/3.15.1","https://github.com/nodeca/js-yaml/releases/tag/4.3.1","https://github.com/nodeca/js-yaml/releases/tag/5.2.1","https://github.com/nodeca/js-yaml/security/advisories/GHSA-724g-mxrg-4qvm"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-59870","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Modified","weaknesses":["CWE-407","CWE-770"],"productCriteria":["cpe:2.3:a:nodeca:js-yaml:*:*:*:*:*:node.js:*:*"],"sourceDates":{"published":"2026-07-08T16:16:33.580","lastModified":"2026-10-06T16:17:08.490"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-59870","identifiers":["CVE-2026-59870"]},"retained":false,"historicalAffected":[]}],"coverage":[]}