CVE-2026-53550 (GCVE-0-2026-53550)

Vulnerability from cvelistv5 – Published: 2026-06-22 14:59 – Updated: 2026-06-29 15:06
VLAI
Title
js-yaml: Quadratic-complexity DoS in merge key handling via repeated aliases
Summary
js-yaml is a JavaScript YAML parser and dumper. Prior to 4.2.0 and 3.15.0, a crafted YAML document can trigger algorithmic CPU exhaustion in js-yaml merge-key processing (<<) by repeating the same alias many times in a merge sequence. This causes quadratic parse-time behavior relative to input size and can block a Node.js worker/event loop for seconds with a relatively small payload (tens of KB), resulting in denial of service. The issue is in merge handling inside lib/loader.js. This vulnerability is fixed in 4.2.0 and 3.15.0.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-23 16:05 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7926 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nodeca js-yaml Affected: >= 4.0.0, < 4.2.0
Affected: < 3.15.0
guessed Create a notification for this product.
Show details on NVD website
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