Prototype Pollution in Nodeca Js-yaml

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 un…

Vulnerability class: Prototype Pollution

EPSS: 0.000 (10.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-64718?
CVE-2025-64718 is a medium-severity vulnerability in Nodeca Js-yaml, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 5.3/10. Published 2025-11-13.
How severe is CVE-2025-64718?
Medium severity. CVSS v3 base score is 5.3 out of 10.