#VU70525 Absolute Path Traversal in Avast Antivirus and AVG Antivirus - CVE-2022-4173

Vulnerability identifier: #VU70525

Vulnerability risk: Low

CVSSv4.0: 7.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2022-4173

CWE-ID: CWE-36

Exploitation vector: Local

Exploit availability: Yes

Vulnerable software:
Avast Antivirus
Client/Desktop applications / Antivirus software/Personal firewalls
AVG Antivirus
Client/Desktop applications / Antivirus software/Personal firewalls

Vendor: Avast Software s.r.o.

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to insecure file path processing within the malware removal functionality. A local user can remove arbitrary files on the system and escalate privileges.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Avast Antivirus: before 22.10

AVG Antivirus: before 22.10

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External links
https://support.norton.com/sp/static/external/tools/security-advisories.html
https://i.blackhat.com/EU-22/Wednesday-Briefings/EU-22-Yair-Aikido-Turning-EDRs-to-Malicious-Wipers.pdf

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.