ZDI-25-256: Avast Free Antivirus Integer Overflow Local Privilege Escalation Vulnerability

Published Apr 24, 2025
·
Updated

This vulnerability allows local attackers to escalate privileges on affected installations of Avast Free Antivirus. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The ZDI has assigned a CVSS rating of 8.8. The following CVEs are assigned: CVE-2025-3500.

Affected Software

1 affected component
Avast Free Antivirus

Event History

Apr 24, 2025
Advisory Published
via ZDI·05:00 AM
Data Sourced
via ZDI·05:00 AM
Description
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Frequently Asked Questions

1

What is the severity of ZDI-25-256?

ZDI-25-256 has been assigned a CVSS rating indicating a critical risk due to its potential for privilege escalation.

2

How do I fix ZDI-25-256?

To mitigate ZDI-25-256, users should update Avast Free Antivirus to the latest version where the vulnerability has been patched.

3

Who is affected by ZDI-25-256?

ZDI-25-256 affects users of Avast Free Antivirus specifically on systems where low-privileged code can be executed.

4

What kind of attack does ZDI-25-256 involve?

ZDI-25-256 enables local attackers to escalate privileges after executing low-privileged code on the vulnerable system.

5

What steps should I take if I suspect ZDI-25-256 has been exploited?

If you suspect that ZDI-25-256 has been exploited, you should immediately secure your system, remove any unauthorized access, and update your antivirus software.

Contact

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