VDB-310442 · CVE-2025-4134 · GCVE-0-2025-4134

Avast Business Antivirus 4.5.1 on Linux do_update_vps file access

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Avast Business Antivirus 4.5.1 on Linux. It has been declared as critical. Affected by this vulnerability is the function do_update_vps. Such manipulation leads to file access. This vulnerability is uniquely identified as CVE-2025-4134. Local access is required to approach this attack. No exploit exists.

Detailsinfo

A vulnerability was found in Avast Business Antivirus 4.5.1 on Linux and classified as critical. Affected by this issue is the function do_update_vps. The manipulation with an unknown input leads to a file access vulnerability. Using CWE to declare the problem leads to CWE-552. The product makes files or directories accessible to unauthorized actors, even though they should not be. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was disclosed by Nông Hoàng Tú. The advisory is available at gendigital.com. This vulnerability is handled as CVE-2025-4134 since 04/30/2025. The exploitation is known to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1083 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Anti-Malware Software

Vendor

Avast

Name

Business Antivirus

Version

4.5.1

License

free

CPE 2.3info

🔍

CPE 2.2info

🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.3
CNA Vector (NLOK): 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: File access
CWE: CWE-552 / CWE-425
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

04/30/2025 🔍
05/28/2025 +28 days 🔍
05/28/2025 +0 days 🔍
05/28/2025 +0 days 🔍

Sourcesinfo

Advisory: gendigital.com
Researcher: Nông Hoàng Tú
Status: Not defined

CVE: CVE-2025-4134 (🔍)
GCVE (CVE): GCVE-0-2025-4134
GCVE (VulDB): GCVE-100-310442

Entryinfo

Created: 05/28/2025 16:49
Changes: 05/28/2025 16:49 (65)
Complete: 🔍
Cache ID: 216::103