js-yaml is a JavaScript YAML parser and dumper. In js-yaml 4.1.0 and below, it's possible for an attacker to modify the prototype of the result of a parsed yaml document via prototype pollution (`__proto__`). All users who parse untrusted yaml documents may be impacted. The problem is patched in js-yaml 4.1.1. Users can protect against this kind of attack on the server by using `node --disable-proto=delete` or `deno` (in Deno, pollution protection is on by default).
Metrics
Affected Vendors & Products
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| Js-yaml |
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References
History
Fri, 14 Nov 2025 09:30:00 +0000
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Js-yaml
Js-yaml js-yaml |
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| Vendors & Products |
Js-yaml
Js-yaml js-yaml |
Thu, 13 Nov 2025 17:15:00 +0000
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| Metrics |
ssvc
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Thu, 13 Nov 2025 15:45:00 +0000
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| Description | js-yaml is a JavaScript YAML parser and dumper. In js-yaml 4.1.0 and below, it's possible for an attacker to modify the prototype of the result of a parsed yaml document via prototype pollution (`__proto__`). All users who parse untrusted yaml documents may be impacted. The problem is patched in js-yaml 4.1.1. Users can protect against this kind of attack on the server by using `node --disable-proto=delete` or `deno` (in Deno, pollution protection is on by default). | |
| Title | js-yaml has prototype pollution in merge (<<) | |
| Weaknesses | CWE-1321 | |
| References |
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| Metrics |
cvssV3_1
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MITRE
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2025-11-13T16:18:39.270Z
Reserved: 2025-11-10T14:07:42.922Z
Link: CVE-2025-64718
Vulnrichment
Updated: 2025-11-13T16:18:34.960Z
NVD
Status : Received
Published: 2025-11-13T16:15:57.153
Modified: 2025-11-13T16:15:57.153
Link: CVE-2025-64718
Redhat
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