CVE Vulnerabilities

CVE-2021-28860

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Published: May 03, 2021 | Modified: Dec 10, 2021
CVSS 3.x
9.1
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
CVSS 2.x
6.4 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

In Node.js mixme, prior to v0.5.1, an attacker can add or alter properties of an object via proto through the mutate() and merge() functions. The polluted attribute will be directly assigned to every object in the program. This will put the availability of the program at risk causing a potential denial of service (DoS).

Weakness

The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.

Affected Software

Name Vendor Start Version End Version
Mixme Adaltas * *

Extended Description

By adding or modifying attributes of an object prototype, it is possible to create attributes that exist on every object, or replace critical attributes with malicious ones. This can be problematic if the product depends on existence or non-existence of certain attributes, or uses pre-defined attributes of object prototype (such as hasOwnProperty, toString or valueOf). This weakness is usually exploited by using a special attribute of objects called proto, constructor or prototype. Such attributes give access to the object prototype. This weakness is often found in code that assigns object attributes based on user input, or merges or clones objects recursively.

Potential Mitigations

References