Inefficient Algorithmic Complexity Affecting js-yaml package, versions <4.2.0
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-JS-JSYAML-17342520
- published16 Jun 2026
- disclosed15 Jun 2026
- credit0xbughunter
Introduced: 15 Jun 2026
NewCVE-2026-53550 (opens in a new tab)How to fix?
Upgrade js-yaml to version 4.2.0 or higher.
Overview
js-yaml is a human-friendly data serialization language.
Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity in the storeMappingPair() function in loader.js when handling repeated aliases in merge sequences. An attacker can exhaust CPU resources and significantly degrade service availability by submitting malicious YAML documents.