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

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad de desbordamiento de búfer basado en pila fue encontrada en los Clientes VPN en el ADM. El problema se deriva del uso de sscanf() sin límites y el paso de datos controlados por el usuario directamente a printf(). Debido a la falta de protecciones PIE y Stack Canary, un atacante remoto autenticado puede explotar estas para ejecutar código arbitrario como el usuario del servidor web. Los productos y versiones afectados incluyen: desde ADM 4.1.0 hasta ADM 4.3.3.RR42 así como desde ADM 5.0.0 hasta ADM 5.1.2.REO1.

Information

Published : 2026-04-20 07:16

Updated : 2026-10-26 21:10

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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