Prototype Pollution Vulnerability in js-yaml by Nodeca
CVE-2025-64718

5.3MEDIUM

Key Information:

Vendor

Nodeca

Status
Js-yaml
Vendor
CVE Published:
13 November 2025

What is CVE-2025-64718?

The js-yaml library, a popular JavaScript YAML parser and dumper, contains a vulnerability that allows attackers to manipulate the prototype of parsed YAML documents through a technique known as prototype pollution. This affects all users handling untrusted YAML inputs. The flaw has been addressed in js-yaml version 4.1.1, and users are encouraged to upgrade. Additional protection measures can be implemented by running Node.js with the '--disable-proto=delete' option or by using Deno, which offers built-in protection against prototype pollution.

Affected Version(s)

js-yaml < 4.1.1

References

https://github.com/nodeca/js-yaml/security/advisories/GHS...
x_refsource_CONFIRM
https://github.com/nodeca/js-yaml/commit/383665ff4248ec21...
x_refsource_MISC

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

JSON
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CVE-2025-64718 : Prototype Pollution Vulnerability in js-yaml by Nodeca