CVE-2021-34858 Memory corruption in TeamViewer

High 7.8 Published 13 Jan 2022 Updated 4 Aug 2024

Remote attackers can execute arbitrary code by tricking users into opening malicious TVS files due to improper input validation.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2021-34858?

CVE-2021-34858 is a high-severity memory corruption vulnerability in TeamViewer, published on 13 Jan 2022. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of TeamViewer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of TVS files. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated structure. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-13606.

Weakness: CWE-125

Which versions are affected by CVE-2021-34858?

It affects 1 product.

Products include Teamviewer Teamviewer.

How do I fix CVE-2021-34858?

No fix has been published for CVE-2021-34858 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-34858 being exploited?

There is no known exploitation of CVE-2021-34858 in the wild and no public exploit code.

Sources

Also known as GHSA-65hf-6m93-q9jf.