CVE-2021-27241: Avast Premium Security AvastSvc Directory Junction Denial-of-Service Vulnerability
This vulnerability allows local attackers to delete arbitrary directories on affected installations of Avast Premium Security 20.8.2429 (Build 20.8.5653.561). An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the AvastSvc.exe module. By creating a directory junction, an attacker can abuse the service to delete a directory. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-12082.
Other sources
This vulnerability allows local attackers to delete arbitrary directories on affected installations of Avast Premium Security. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the AvastSvc.exe module. By creating a directory junction, an attacker can abuse the service to delete a directory. An attacker can leverage this vulnerability to create a denial-of-service condition on the system.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2021-27241?
CVE-2021-27241 is a vulnerability in Avast Premium Security that allows local attackers to delete arbitrary directories on affected installations.
How can this vulnerability be exploited?
To exploit this vulnerability, an attacker must first obtain the ability to execute low-privileged code on the target system.
What is the severity of CVE-2021-27241?
CVE-2021-27241 has a severity rating of 6.1 (Medium).
What software versions are affected by CVE-2021-27241?
CVE-2021-27241 affects Avast Premium Security 20.8.2429.
Is there a fix for CVE-2021-27241?
A fix for CVE-2021-27241 is not currently available. It is recommended to update to the latest version of Avast Premium Security once a patch is released.