CVE-2026-59869

js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 before 3.15.0 and from 4.0.0 before 4.3.0, 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 versions 3.15.0 and 4.3.0.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7	Patch
https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4	Patch
https://github.com/nodeca/js-yaml/releases/tag/3.15.0	Release Notes
https://github.com/nodeca/js-yaml/releases/tag/4.3.0	Release Notes
https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m	Exploit Vendor Advisory
https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:nodeca:js-yaml::::::node.js::*
	cpe:2.3:a:nodeca:js-yaml::::::node.js::*

History

No history.

Information

Published : 2026-07-08 16:16

Updated : 2026-07-13 15:05

NVD link : CVE-2026-59869

Mitre link : CVE-2026-59869

CVE.ORG link : CVE-2026-59869

JSON object : View

Products Affected

nodeca

js-yaml

CWE

CWE-407

Inefficient Algorithmic Complexity

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