Vulnerability · Published May 28, 2025 · Assigned by NLOK
CVE-2025-4134Lack of file validation in Avast Business Antivirus for Linux allows writing untrusted update files
High 7.3
In plain English
A high-severity security flaw in Avast Business Antivirus from Avast. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 12% of all known vulnerabilities).
Severity (CVSS 3.1)7.3High
Exploit odds (30 days)0.2%top 87.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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 (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Avast | Avast Business Antivirus | 4.5.1 |
Weakness: CWE-552 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H