CVE-2026-11771
HIGH
7,0
Source: [email protected]
Attack Vector: network
Attack Complexity: high
Privileges Required: none
User Interaction: passive
Confidentiality: N/A
Integrity: N/A
Availability: N/A
Description
AI Translation Available
OpenVPN version 2.1.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows attackers via an off-by-one buffer write in the NTLM proxy authentication to potentially cause a crash via a crafted NTLM response from a malicious proxy server
121
Stack-based Buffer Overflow
DraftCommon Consequences
Security Scopes Affected:
Availability
Integrity
Confidentiality
Access Control
Other
Potential Impacts:
Modify Memory
Dos: Crash, Exit, Or Restart
Dos: Resource Consumption (Cpu)
Dos: Resource Consumption (Memory)
Execute Unauthorized Code Or Commands
Bypass Protection Mechanism
Other
Applicable Platforms
Languages:
Memory-Unsafe, C, C++
193
Off-by-one Error
DraftCommon Consequences
Security Scopes Affected:
Availability
Integrity
Confidentiality
Access Control
Potential Impacts:
Dos: Crash, Exit, Or Restart
Dos: Resource Consumption (Cpu)
Dos: Resource Consumption (Memory)
Dos: Instability
Modify Memory
Execute Unauthorized Code Or Commands
Bypass Protection Mechanism
Applicable Platforms
Languages:
C, Not Language-Specific
787
Out-of-bounds Write
DraftCommon Consequences
Security Scopes Affected:
Integrity
Availability
Other
Potential Impacts:
Modify Memory
Execute Unauthorized Code Or Commands
Dos: Crash, Exit, Or Restart
Unexpected State
Applicable Platforms
Languages:
Memory-Unsafe, C, C++, Assembly
Technologies:
ICS/OT
https://community.openvpn.net/ReleaseHistory#openvpn-2621-released-1-july-2026
https://community.openvpn.net/ReleaseHistory#openvpn-275-released-1-july-2026
https://community.openvpn.net/Security%20Announcements/CVE-2026-11771