js-yaml has prototype pollution in merge (<<)
Vulnerability Description
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).
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
- https://github.com/nodeca/js-yaml/security/advisories/GHSA-mh29-5h37-fv8m
- https://github.com/nodeca/js-yaml/issues/730#issuecomment-3549635876
- https://github.com/nodeca/js-yaml/commit/383665ff4248ec2192d1274e934462bb30426879
- https://github.com/nodeca/js-yaml/commit/5278870a17454fe8621dbd8c445c412529525266
Affected Vendor
nodeca
View all reports →Affected Software
Timeline
CVSS Vectors
Weaknesses (CWE)
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.