CVE-2025-4134: Lack of file validation in Avast Business Antivirus for Linux allows writing untrusted update files

Severity: high (CVSS 7.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-05-28 · updated 2026-06-17
Weakness: CWE-552

Description

Lack of file validation in do_update_vps in Avast Business Antivirus for Linux 4.5 on Linux allows local user to spoof or tamper with the update file via an unverified file write.

Affected products

Avast Business Antivirus: 4.5.1

References

https://www.gendigital.com/us/en/contact-us/security-advisories/

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