CVE-2026-59868: CWE-407: Inefficient Algorithmic Complexity in nodeca js-yaml
js-yaml versions from 5.0.0 up to but not including 5.2.0 have an inefficient algorithmic complexity issue when merge keys are enabled. This causes the parser to spend quadratic CPU time parsing certain YAML documents that grow linearly in size, specifically when a chain of mappings merges the previous one. This vulnerability can lead to denial of service due to excessive CPU consumption. The issue is fixed in version 5.2.0.
AI Analysis
Technical Summary
The js-yaml JavaScript library versions >=5.0.0 and <5.2.0 exhibit a CWE-407 inefficient algorithmic complexity vulnerability when merge keys are enabled. Parsing a YAML document with a chain of mappings that merge the previous one causes the CPU time to grow quadratically relative to the document size, which grows only linearly. This can degrade performance and potentially cause denial of service. The vulnerability is resolved in version 5.2.0.
Potential Impact
This vulnerability impacts availability by causing excessive CPU usage during YAML parsing, potentially leading to denial of service conditions. There is no impact on confidentiality or integrity. The CVSS score is 5.3 (medium severity), reflecting the limited scope of impact to availability only and the network attack vector with no privileges or user interaction required.
Mitigation Recommendations
Upgrade js-yaml to version 5.2.0 or later, where this inefficient algorithmic complexity issue is fixed. No other mitigations are indicated or required.
CVE-2026-59868: CWE-407: Inefficient Algorithmic Complexity in nodeca js-yaml
Description
js-yaml versions from 5.0.0 up to but not including 5.2.0 have an inefficient algorithmic complexity issue when merge keys are enabled. This causes the parser to spend quadratic CPU time parsing certain YAML documents that grow linearly in size, specifically when a chain of mappings merges the previous one. This vulnerability can lead to denial of service due to excessive CPU consumption. The issue is fixed in version 5.2.0.
CVSS v3.1
Score 5.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The js-yaml JavaScript library versions >=5.0.0 and <5.2.0 exhibit a CWE-407 inefficient algorithmic complexity vulnerability when merge keys are enabled. Parsing a YAML document with a chain of mappings that merge the previous one causes the CPU time to grow quadratically relative to the document size, which grows only linearly. This can degrade performance and potentially cause denial of service. The vulnerability is resolved in version 5.2.0.
Potential Impact
This vulnerability impacts availability by causing excessive CPU usage during YAML parsing, potentially leading to denial of service conditions. There is no impact on confidentiality or integrity. The CVSS score is 5.3 (medium severity), reflecting the limited scope of impact to availability only and the network attack vector with no privileges or user interaction required.
Mitigation Recommendations
Upgrade js-yaml to version 5.2.0 or later, where this inefficient algorithmic complexity issue is fixed. No other mitigations are indicated or required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-07T15:41:53.607Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4e73c2c9d9e3dbe36042af
Added to database: 07/08/2026, 15:58:58 UTC
Last enriched: 07/08/2026, 16:14:35 UTC
Last updated: 07/09/2026, 01:40:51 UTC
Views: 6
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