Prototype pollution vulnerability in ‘keyget’ versions 1.0.0 through 2.2.0 allows attacker to cause a denial of service and may lead to remote code execution.
The npm module ‘keyget’ can be abused by Prototype Pollution vulnerability since the function ‘setByPath()’ 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 setByPath()
function accepts three arguments target, path, value
. Due to the absence of validation, at values passed into path, value
an attacker can supply a malicious value by adjusting the path
value to include the __proto__
property. Since there is no validation before assigning property to check whether the assigned path
is the Object’s own property or not, the property polluted
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 polluted
the value would be substituted as “true” as it had been polluted.
var keyget = require("keyget")
keyget.set({}, '__proto__.polluted', 'true');
console.log(polluted);