// For flags

CVE-2025-4134

Lack of file validation in Avast Business Antivirus for Linux allows writing untrusted update files

Severity Score

7.3
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track*
*SSVC
Descriptions

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.

*Credits: FIS Securtiy, Nông Hoàng Tú
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
Single
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Track*
Exploitation
None
Automatable
No
Tech. Impact
Total
* Organization's Worst-case Scenario
Timeline
  • 2025-04-30 CVE Reserved
  • 2025-05-28 CVE Published
  • 2025-05-28 CVE Updated
  • 2025-08-04 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-552: Files or Directories Accessible to External Parties
CAPEC
  • CAPEC-148: Content Spoofing
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Avast
Search vendor "Avast"
 Avast
Search vendor "Avast" for product "Avast"
*-
Affected