CVE-2021-34420

Zoom Windows installation executable signature bypass

Description

The Zoom Client for Meetings for Windows installer before version 5.5.4 does not properly verify the signature of files with .msi, .ps1, and .bat extensions. This could lead to a malicious actor installing malicious software on a customer’s computer.

Category

4.7
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.17%
Vendor Advisory zoom.us
Affected: Zoom Video Communications Inc Zoom Client for Meetings for Windows
Published at:
Updated at:

References

Link Tags
https://explore.zoom.us/en/trust/security/security-bulletin vendor advisory
https://medium.com/manomano-tech/a-red-team-operation-leveraging-a-zero-day-vulnerability-in-zoom-80f57fb0822e third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-34420?
CVE-2021-34420 has been scored as a medium severity vulnerability.
How to fix CVE-2021-34420?
To fix CVE-2021-34420, 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-2021-34420 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34420 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34420?
CVE-2021-34420 affects Zoom Video Communications Inc Zoom Client for Meetings for Windows.
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