CVE-2020-25289 : Exploit Details and Defense Strategies

AVAST SecureLine VPN before version 5.6.4982.470 is vulnerable to a local file writing issue via an Object Manager symbolic link in the log directory.

Understanding CVE-2020-25289

This CVE describes a vulnerability in the VPN service of AVAST SecureLine that allows local users to write to arbitrary files due to weak permissions in the log directory.

What is CVE-2020-25289?

The vulnerability in AVAST SecureLine VPN before version 5.6.4982.470 enables local users to manipulate symbolic links in the log directory, leading to unauthorized file writing.

The Impact of CVE-2020-25289

The vulnerability could be exploited by local attackers to write to sensitive files, potentially leading to unauthorized access or privilege escalation.

Technical Details of CVE-2020-25289

AVAST SecureLine VPN is affected by a file writing vulnerability due to weak permissions in the log directory.

Vulnerability Description

The issue allows local users to write to arbitrary files by exploiting an Object Manager symbolic link in the log directory.

Affected Systems and Versions

Product: AVAST SecureLine VPN
Versions affected: Before 5.6.4982.470

Exploitation Mechanism

Attackers can create symbolic links in the log directory to write to files with weak permissions, potentially gaining unauthorized access.

Mitigation and Prevention

To address CVE-2020-25289, immediate steps and long-term security practices are recommended.

Immediate Steps to Take

Update AVAST SecureLine VPN to version 5.6.4982.470 or later.
Restrict access to the log directory to prevent unauthorized file writing.

Long-Term Security Practices

Regularly monitor and audit file permissions and symbolic links in critical directories.
Educate users on secure file handling practices to prevent exploitation.

Patching and Updates

Ensure timely installation of security patches and updates for AVAST SecureLine VPN to mitigate the vulnerability.