Prototype pollution vulnerability in βdsetβ versions 1.0.0 through 2.0.1 allows attacker to cause a denial of service and may lead to remote code execution.
The NPM module βdsetβ can be abused by Prototype Pollution vulnerability since the function βexport ()β did not check for the type of object before assigning value to the property. Due to this flaw an attacker could create a non-existent property or able to manipulate the property which leads to Denial of Service or potentially Remote code execution.
The export function accepts three arguments obj, keys, val
. Due to the absence of validation, at values passed into keys, val
arguments, an attacker can supply a malicious value by adjusting the keys
value to include the __proto__
property. Since there is no validation before assigning property to check whether the assigned keys
is the Objectβs own property or not, the property isAdmin
will be directly be assigned to the empty obj({}) thereby polluting the Object prototype. Later in the code, if there is a check to validate isAdmin
the valued would be substituted as βtrueβ as it had been polluted.
const dset = require('dset');
var obj = {}
console.log("Before : " + obj.isAdmin);
dset(obj, '__proto__.polluted', true);
console.log("After : " + obj.polluted);
github.com/lukeed/dset/blob/50a6ead172d1466a96035eff00f8eb465ccd050a/src/index.js#L6
github.com/lukeed/dset/commit/2b9ec49e231107b1a83b04a1bc1a66a8d14cea1c
github.com/lukeed/dset/issues/11
nvd.nist.gov/vuln/detail/CVE-2020-28277
web.archive.org/web/20210104204657/https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28277