CVE-2026-59870
Last modified
CVE-2026-59870 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.29% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Nodeca | Js-Yaml | >= 5.0.0, < 5.2.1 |
References
- https://github.com/nodeca/js-yaml/releases/tag/5.2.1Release Notes
- https://github.com/nodeca/js-yaml/security/advisories/GHSA-724g-mxrg-4qvmExploit, Vendor Advisory
- https://github.com/nodeca/js-yaml/security/advisories/GHSA-724g-mxrg-4qvmExploit, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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