CVE-2026-59870 (GCVE-0-2026-59870)

Vulnerability from cvelistv5 – Published: 2026-07-08 15:13 – Updated: 2026-10-06 15:07
VLAI
Title
js-yaml quadratic-complexity denial of service via YAML11_SCHEMA !!omap parsing
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 15:50 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8017 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nodeca js-yaml Affected: >= 5.0.0, < 5.2.1
Affected: >= 3.0.0, < 3.15.1
Affected: >= 4.0.0, < 4.3.1
guessed Create a notification for this product.
Show details on NVD website
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}



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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.