CVE-2021-34858

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.

Category

7.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 1.40% Top 25%
Vendor Advisory teamviewer.com
Affected: TeamViewer TeamViewer
Published at:
Updated at:

References

Link Tags
https://community.teamviewer.com/English/discussion/117794/august-updates-security-patches/p1 vendor advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-1001/ vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-34858?
CVE-2021-34858 has been scored as a high severity vulnerability.
How to fix CVE-2021-34858?
To fix CVE-2021-34858, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-34858 being actively exploited in the wild?
It is possible that CVE-2021-34858 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34858?
CVE-2021-34858 affects TeamViewer TeamViewer.
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