CVE-2026-59868

js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.0, when merge keys are enabled, 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 version 5.2.0.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/nodeca/js-yaml/commit/3105455b81dee69e0fd36e09ac0b2ccfdb54adc1	Patch
https://github.com/nodeca/js-yaml/releases/tag/5.2.0	Release Notes
https://github.com/nodeca/js-yaml/security/advisories/GHSA-g796-fgmg-93mv	Exploit Vendor Advisory
https://github.com/nodeca/js-yaml/security/advisories/GHSA-g796-fgmg-93mv	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-08 16:16

Updated : 2026-07-13 15:06

NVD link : CVE-2026-59868

Mitre link : CVE-2026-59868

CVE.ORG link : CVE-2026-59868

JSON object : View

Products Affected

nodeca

js-yaml

CWE

CWE-407

Inefficient Algorithmic Complexity

CWE-770

Allocation of Resources Without Limits or Throttling

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