Openvpn: >> Openvpn Security Vulnerabilities
OpenVPN 2.1 until v2.4.12 and v2.5.6 may enable authentication bypass in external authentication plug-ins when more than one of them makes use of deferred authentication replies, which allows an external user to be granted access with only partially correct credentials.
CVSS Score
9.8
EPSS Score
0.005
Published
2022-03-18
OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same hostname found in the verify-x509-name option in a client configuration.
CVSS Score
7.4
EPSS Score
0.001
Published
2021-07-12
OpenVPN before version 2.5.3 on Windows allows local users to load arbitrary dynamic loadable libraries via an OpenSSL configuration file if present, which allows the user to run arbitrary code with the same privilege level as the main OpenVPN process (openvpn.exe).
CVSS Score
7.8
EPSS Score
0.001
Published
2021-07-02
OpenVPN 2.5.1 and earlier versions allows a remote attackers to bypass authentication and access control channel data on servers configured with deferred authentication, which can be used to potentially trigger further information leaks.
CVSS Score
7.5
EPSS Score
0.004
Published
2021-04-26
An issue was discovered in OpenVPN 2.4.x before 2.4.9. An attacker can inject a data channel v2 (P_DATA_V2) packet using a victim's peer-id. Normally such packets are dropped, but if this packet arrives before the data channel crypto parameters have been initialized, the victim's connection will be dropped. This requires careful timing due to the small time window (usually within a few seconds) between the victim client connection starting and the server PUSH_REPLY response back to the client. This attack will only work if Negotiable Cipher Parameters (NCP) is in use.
CVSS Score
3.7
EPSS Score
0.024
Published
2020-04-27
openvpnserv.exe (aka the interactive service helper) in OpenVPN 2.4.x before 2.4.6 allows a local attacker to cause a double-free of memory by sending a malformed request to the interactive service. This could cause a denial-of-service through memory corruption or possibly have unspecified other impact including privilege escalation.
CVSS Score
7.8
EPSS Score
0.001
Published
2018-05-01
A cross-protocol scripting issue was discovered in the management interface in OpenVPN through 2.4.5. When this interface is enabled over TCP without a password, and when no other clients are connected to this interface, attackers can execute arbitrary management commands, obtain sensitive information, or cause a denial of service (SIGTERM) by triggering XMLHttpRequest actions in a web browser. This is demonstrated by a multipart/form-data POST to http://localhost:23000 with a "signal SIGTERM" command in a TEXTAREA element. NOTE: The vendor disputes that this is a vulnerability. They state that this is the result of improper configuration of the OpenVPN instance rather than an intrinsic vulnerability, and now more explicitly warn against such configurations in both the management-interface documentation, and with a runtime warning
CVSS Score
9.1
EPSS Score
0.004
Published
2018-03-16
OpenVPN versions before 2.3.3 and 2.4.x before 2.4.4 are vulnerable to a buffer overflow vulnerability when key-method 1 is used, possibly resulting in code execution.
CVSS Score
9.8
EPSS Score
0.051
Published
2017-10-04
OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to remote denial-of-service when receiving malformed IPv6 packet.
CVSS Score
7.5
EPSS Score
0.01
Published
2017-06-27
OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to denial-of-service and/or possibly sensitive memory leak triggered by man-in-the-middle attacker.
CVSS Score
7.4
EPSS Score
0.006
Published
2017-06-27