← CVE Intelligence

CVE-2026-59870

js-yaml quadratic-complexity denial of service via YAML11_SCHEMA !!omap parsing PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / productVersions
nodeca / js-yamlaffected >= 5.0.0, < 5.2.1; affected >= 3.0.0, < 3.15.1; affected >= 4.0.0, < 4.3.1

CWE

CWE-407

References

ADP enrichment

CISA-ADP

No English description supplied.