CVE-2026-6643

A stack-based buffer overflow vulnerability was found in the VPN Clients on the ADM. The issue stems from the use of unbounded sscanf() and passing user-controlled data directly to printf(). Due to the lack of PIE and Stack Canary protections, an authenticated remote attacker can exploit these to execute arbitrary code as the web server user. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.RR42 as well as from ADM 5.0.0 through ADM 5.1.2.REO1.

CVSS v3 9.9 CRITICAL

9.9^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://www.asustor.com/security/security_advisory_detail?id=54	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:asustor:data_master::::::::
	cpe:2.3:o:asustor:data_master::::::::

History

22 Apr 2026, 14:43

Type	Values Removed	Values Added
CPE		cpe:2.3:o:asustor:data_master::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.9
First Time		Asustor data Master Asustor
References	~~() https://www.asustor.com/security/security_advisory_detail?id=54 -~~	() https://www.asustor.com/security/security_advisory_detail?id=54 - Vendor Advisory

20 Apr 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-20 07:16

Updated : 2026-04-22 14:43

NVD link : CVE-2026-6643

Mitre link : CVE-2026-6643

CVE.ORG link : CVE-2026-6643

JSON object : View

Products Affected

asustor

data_master

CWE

CWE-121

Stack-based Buffer Overflow

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