Affected versions of yargs-parser are vulnerable to prototype pollution. Arguments are not properly sanitized, allowing an attacker to modify the prototype of Object, causing the addition or modification of an existing property that will exist on all objects.
Parsing the argument --foo.__proto__.bar baz' adds a bar property with value baz to all objects. This is only exploitable if attackers have control over the arguments being passed to yargs-parser.
Recommendation
Upgrade to versions 13.1.2, 15.0.1, 18.1.1 or later.
References
- https://snyk.io/vuln/SNYK-JS-YARGSPARSER-560381
- https://www.npmjs.com/advisories/1500
- https://github.com/yargs/yargs-parser/commit/63810ca1ae1a24b08293a4d971e70e058c7a41e2
- https://nvd.nist.gov/vuln/detail/CVE-2020-7608
- https://github.com/yargs/yargs-parser/commit/1c417bd0b42b09c475ee881e36d292af4fa2cc36
- https://github.com/advisories/GHSA-p9pc-299p-vxgp