CVE-2025-64718
js-yaml is a JavaScript YAML parser and dumper. In js-yaml before 4.1.1 and 3.14.2, 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 and 3.14.2. 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).
- CVSS 3.1
- 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 36% of CVEs (scores of 2026-10-25)
- CWE
- CWE-1321
- Published
- Modified
- Record from
- the NVD, synced
Affected
- nodeca:js-yaml
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-mh29-5h37-fv8m | npm | js-yaml | >=4.0.0 <4.1.1 | 4.1.1 |
| GHSA-mh29-5h37-fv8m | npm | js-yaml | <3.14.2 | 3.14.2 |
References
- https://github.com/nodeca/js-yaml/commit/383665ff4248ec2192d1274e934462bb30426879
- https://github.com/nodeca/js-yaml/commit/5278870a17454fe8621dbd8c445c412529525266
- https://github.com/nodeca/js-yaml/issues/730#issuecomment-3549635876
- https://github.com/nodeca/js-yaml/security/advisories/GHSA-mh29-5h37-fv8m
- https://github.com/advisories/GHSA-mh29-5h37-fv8m