{"cve":"CVE-2026-59869","nvd":{"published":"2026-07-08T16:16:33.423","modified":"2026-10-25T20:10:00.147","status":"Analyzed","description":"js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 before 3.15.0 and from 4.0.0 before 4.3.0, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the previous one. This issue is fixed in versions 3.15.0 and 4.3.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-407"],"references":["https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7","https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4","https://github.com/nodeca/js-yaml/releases/tag/3.15.0","https://github.com/nodeca/js-yaml/releases/tag/4.3.0","https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m"],"products":["nodeca:js-yaml"],"source":"nvd","synced_at":"2026-10-25T23:44:34.550481224+00:00"},"epss":{"cve":"CVE-2026-59869","score":0.00585,"percentile":0.47696,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-52cp-r559-cp3m","url":"https://osv.dev/vulnerability/GHSA-52cp-r559-cp3m","summary":"js-yaml: YAML merge-key chains can force quadratic CPU consumption","modified":"2026-09-10T03:50:12.263307536Z","packages":[{"ecosystem":"npm","name":"js-yaml","purl":"pkg:npm/js-yaml","ranges":[">=3.0.0 <3.15.0"],"fixed":["3.15.0"]},{"ecosystem":"npm","name":"js-yaml","purl":"pkg:npm/js-yaml","ranges":[">=4.0.0 <4.3.0"],"fixed":["4.3.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}