CVE Explorer
CVE-2026-53550
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 vulnerabil
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"product":"js-yaml","vendor":"nodeca","versions":[{"status":"affected","version":">= 4.0.0, < 4.2.0"},{"status":"affected","version":"< 3.15.0"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:a59005836bd2af8a5af462723387b23d42f5f42cb929e0ab99ae75cc6a9723c2 · sha256:2db862a275e00fc5… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.1"},"metric_type":"cvssV3_1"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:a59005836bd2af8a5af462723387b23d42f5f42cb929e0ab99ae75cc6a9723c2 · sha256:2db862a275e00fc5… · /containers/cna/metrics/0/cvssV3_1
CWE assertions
1 source assertion{"cweId":"CWE-407","description":"CWE-407: Inefficient Algorithmic Complexity","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:a59005836bd2af8a5af462723387b23d42f5f42cb929e0ab99ae75cc6a9723c2 · sha256:2db862a275e00fc5… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-h67p-54hq-rp68","tags":["x_refsource_CONFIRM"],"url":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-h67p-54hq-rp68"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:a59005836bd2af8a5af462723387b23d42f5f42cb929e0ab99ae75cc6a9723c2 · sha256:2db862a275e00fc5… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.