CVE-2021-27241

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.

CVSS v3 6.1 MEDIUM
CVSS v2.0 3.6 LOW

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

3.6^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:N/I:P/A:P

Exploitability : 3.9 / Impact : 4.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://www.zerodayinitiative.com/advisories/ZDI-21-208/	Third Party Advisory VDB Entry
https://www.zerodayinitiative.com/advisories/ZDI-21-208/	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

cpe:2.3:a:avast:premium_security:20.8.2429:*:*:*:*:*:*:*

History

21 Nov 2024, 05:57

Type	Values Removed	Values Added
References	~~() https://www.zerodayinitiative.com/advisories/ZDI-21-208/ - Third Party Advisory, VDB Entry~~	() https://www.zerodayinitiative.com/advisories/ZDI-21-208/ - Third Party Advisory, VDB Entry

Information

Published : 2021-03-29 21:15

Updated : 2024-11-21 05:57

NVD link : CVE-2021-27241

Mitre link : CVE-2021-27241

CVE.ORG link : CVE-2021-27241

JSON object : View

Products Affected

avast

premium_security

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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