{"id":"CVE-2026-59868","aliases":["GHSA-g796-fgmg-93mv"],"url":"https://o3.security/vulnerability/CVE-2026-59868","summary":"js-yaml: YAML merge-key chains can force quadratic CPU consumption","details":"js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.0, when merge keys are enabled, 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 version 5.2.0.","published":"2026-07-08T15:18:19.422Z","modified":"2026-08-12T03:51:08.347940150Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"epss":{"score":0.00644,"percentile":0.48121,"asOf":"2026-08-25"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"js-yaml","fixedVersion":"5.2.0"}],"fix":{"url":"https://github.com/nodeca/js-yaml/commit/3105455b81dee69e0fd36e09ac0b2ccfdb54adc1","label":"nodeca/js-yaml@3105455"},"references":[{"type":"WEB","url":"https://github.com/nodeca/js-yaml/releases/tag/5.2.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59868.json"},{"type":"ADVISORY","url":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-g796-fgmg-93mv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59868"},{"type":"FIX","url":"https://github.com/nodeca/js-yaml/commit/3105455b81dee69e0fd36e09ac0b2ccfdb54adc1"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:08.347940150Z"}}