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[GHSA-mh29-5h37-fv8m] js-yaml has prototype pollution in merge (<<) #6420

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Merged
advisory-database merged 1 commit into from
Nov 17, 2025
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[GHSA-mh29-5h37-fv8m] js-yaml has prototype pollution in merge (<<) #6420

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29 changes: 26 additions & 3 deletions advisories/github-reviewed/2025/11/GHSA-mh29-5h37-fv8m/GHSA-mh29-5h37-fv8m.json
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Original file line number Diff line number Diff line change
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{
"schema_version": "1.4.0",
"id": "GHSA-mh29-5h37-fv8m",
"modified": "2025-11-14T14:29:48Z",
"modified": "2025-11-14T14:29:49Z",
"published": "2025-11-14T14:29:48Z",
"aliases": [
"CVE-2025-64718"
],
"summary": "js-yaml has prototype pollution in merge (<<)",
"details": "### Impact\n\nIn 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.\n\n### Patches\n\nProblem is patched in js-yaml 4.1.1.\n\n### Workarounds\n\nYou 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).\n\n### References\n\nhttps://cheatsheetseries.owasp.org/cheatsheets/Prototype_Pollution_Prevention_Cheat_Sheet.html",
"details": "### Impact\n\nIn js-yaml 4.1.0 and below (and 3.14.1 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.\n\n### Patches\n\nProblem is patched in js-yaml 4.1.1 and 3.14.2.\n\n### Workarounds\n\nYou 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).\n\n### References\n\nhttps://cheatsheetseries.owasp.org/cheatsheets/Prototype_Pollution_Prevention_Cheat_Sheet.html",
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@mhassan1 mhassan1 Nov 15, 2025 •
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"details": "### Impact\n\nIn js-yaml 4.1.0 and below (and 3.14.1 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.\n\n### Patches\n\nProblem is patched in js-yaml 4.1.1 and 3.14.2.\n\n### Workarounds\n\nYou 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).\n\n### References\n\nhttps://cheatsheetseries.owasp.org/cheatsheets/Prototype_Pollution_Prevention_Cheat_Sheet.html",
"details": "### Impact\n\nIn js-yaml 4.1.0, 4.0.0, and 3.14.1 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.\n\n### Patches\n\nProblem is patched in js-yaml 4.1.1 and 3.14.2.\n\n### Workarounds\n\nYou 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).\n\n### References\n\nhttps://cheatsheetseries.owasp.org/cheatsheets/Prototype_Pollution_Prevention_Cheat_Sheet.html",

"severity": [
{
"type": "CVSS_V3",
Expand All @@ -25,14 +25,33 @@
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
"introduced": "4.0.0"
},
{
"fixed": "4.1.1"
}
]
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "js-yaml"
},
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.14.2"
}
]
}
]
}
],
"references": [
Expand All @@ -48,6 +67,10 @@
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/commit/383665ff4248ec2192d1274e934462bb30426879"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/commit/5278870a17454fe8621dbd8c445c412529525266"
},
{
"type": "PACKAGE",
"url": "https://github.com/nodeca/js-yaml"
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