PT-2026-56491 · Nodeca · Js-Yaml

Published 2026-07-08 · Updated 2026-07-08 · CVE-2026-59870

NVD

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 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. This issue is fixed in version 5.2.1.

Exploit

Fix

Weakness Enumeration

CWE-407

Related Identifiers

CVE-2026-59870

Affected Products

Js-Yaml

References · 4

• 🔥 https://github.com/nodeca/js-yaml/security/advisories/GHSA-724g-mxrg-4qvm · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-59870 · Security Note
• https://github.com/nodeca/js-yaml/releases/tag/5.2.1 · Note
• https://github.com/nodeca/js-yaml/commit/39f3211a2f01b3c6982710cf21434ab7060acefe · Note