CVE-2025-64718

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).

References

https://github.com/nodeca/js-yaml/commit/383665ff4248ec2192d1274e934462bb30426879

https://github.com/nodeca/js-yaml/security/advisories/GHSA-mh29-5h37-fv8m