CVE-2021-27241

Severity CVSS v4.0:

Pending analysis

Type:

CWE-59 Link Following

Publication date:

29/03/2021

Last modified:

01/04/2021

Description

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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H CVSS v3.1 Severity and Metrics:

Base Score: 6.10 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): Low
Availability (A): High

Base Score 3.x

6.10

Severity 3.x

MEDIUM

Vector 2.0

AV:L/AC:L/Au:N/C:N/I:P/A:P CVSS v2.0 Severity and Metrics:

Base Score: 3.60 LOW
Vector: AV:L/AC:L/Au:N/C:N/I:P/A:P

Attack Vector (AV): Local
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): None
Integrity (I): Physical
Availability (A): Physical

Base Score 2.0

3.60

Severity 2.0

LOW

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:avast:premium_security:20.8.2429:::::::*

To consult the complete list of CPE names with products and versions, see this page

References to Advisories, Solutions, and Tools

https://www.zerodayinitiative.com/advisories/ZDI-21-208/