CVE Vulnerabilities

CVE-2021-39205

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

Published: Sep 15, 2021 | Modified: Sep 10, 2022
CVSS 3.x
6.1
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

Jitsi Meet is an open source video conferencing application. Versions prior to 2.0.6173 are vulnerable to client-side cross-site scripting via injecting properties into JSON objects that were not properly escaped. There are no known incidents related to this vulnerability being exploited in the wild. This issue is fixed in Jitsi Meet version 2.0.6173. There are no known workarounds aside from upgrading.

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
Jitsi_meet 8x8 * 2.0.6173 (excluding)

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