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OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences inside HTTP header values, allowing remote attackers to perform HTTP request smuggling when deployed behind a reverse proxy
Insufficient argument validation in OpenVPN 2.7alpha1 through 2.7rc1 allows an attacker to trigger a heap buffer over-read when parsing IP addresses
Improper validation of source IP addresses in OpenVPN version 2.6.0 through 2.6.15 and 2.7alpha1 through 2.7rc1 allows an attacker to open a session from a different IP address which did not initiate the connection resulting in a denial of service for the originating client
An incorrect buffer size calculation in the epoch key generator in OpenVPN ovpn-dco-win version 2.0.0 through 2.8.3 allows a remote authenticated peer to trigger a heap-based buffer overflow and kernel memory corruption via a crafted data packet, resulting in a system crash (denial of service).
An incomplete guard in OpenVPN 2.6.0 through 2.6.20 and 2.7alpha1 through 2.7.4 allows remote authenticated peers to trigger a use-after-free during TLS session promotion, potentially leading to a denial of service or memory leakage
A memory leak in the tls-crypt-v2 client key extraction in OpenVPN 2.5.0 through 2.6.20 and 2.7alpha1 through 2.7.4 allows remote attackers to cause a denial of service (memory exhaustion) via a flood of crafted packets
An incorrect buffer size calculation in the Windows Interactive Service in OpenVPN 2.7alpha1 through 2.7.6 allows local authenticated users to cause memory corruption or disclose sensitive information via crafted NRPT inputs.
The Windows Interactive Service in OpenVPN 2.7alpha1 through 2.7.6 allows local authenticated users to bypass the trusted configuration directory constraint and load arbitrary configuration files via specially crafted paths
OpenVPN 2.5.0 through 2.7.6 on Windows using the tap-windows6 driver allows attackers to trigger an out-of-bounds write via crafted DOMAIN-SEARCH entries
The Windows interactive service in OpenVPN 2.4.0 through 2.6.22 allows local authenticated users to bypass the trusted configuration directory constraint via incorrect file path validation
OpenVPN 2.0.0 through 2.6.22 and 2.7alpha1 through 2.7.6 on Windows allows local authenticated users to cause a denial of service via a NULL DACL on named IPC objects
OpenVPN version 2.5.0 through 2.6.22 and 2.7alpha1 through 2.7.6 on Windows allows local authenticated users to perform a binary planting attack during network configuration steps
An argument parsing issue in OpenVPN 2.1rc10 through 2.6.22 and 2.7alpha1 through 2.7.6 on Windows allows remote authenticated users to execute arbitrary commands via a crafted certificate subject
Retransmissions of ACK packet ID in OpenVPN through 2.6.22 and 2.7.6 allow remote unauthenticated attackers to cause a denial of service via crafted inputs that trigger a timeout integer overflow
A use-after-free vulnerability in the OpenVPN ovpn-dco-win driver version 2.5.0 through 2.8.6 allows local authenticated users to cause a system crash via crafted control messages
The Windows interactive service in OpenVPN 2.4.0 through 2.6.21 and 2.7alpha1 through 2.7.5 allows local authenticated users to bypass the trusted configuration directory constraint and load arbitrary configuration files via crafted options that bypass whitelist checks
OpenVPN 2.7alpha1 through 2.7.5 using mbedTLS allows remote authenticated users to be misidentified by ignoring the configured X.509 username identity lookup field
Improper validation of packet length during tls-crypt-v2 key extraction in OpenVPN 2.6.0 through 2.6.19 and 2.7alpha1 through 2.7.1 allows authenticated attackers to trigger a fatal assertion and cause a denial of service via a specially crafted packet.
A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.
Last updated 8 July 2026
A use-after-free in OpenVPN 2.6.0 through 2.6.20 and 2.7alpha1 through 2.7.4 allows remote authenticated peers to potentially cause a denial of service or leak memory via crafted packets during TLS session promotion or expiry
The Windows interactive service in OpenVPN 2.7alpha1 through 2.7.4 allows remote attackers to cause persistent DNS state pollution or a service crash via a crafted search domain during the disconnection process
Privilege escalation via background service of OpenVPN Connect 3.5.1 through 3.8.1 on macOS allows attackers to execute arbitrary commands with elevated privileges via local IPC channel
Last updated 10 July 2026
A memory leak in OpenVPN version 2.5.0 through 2.5.11, 2.6.0 through 2.6.20 and 2.7alpha1 through 2.7.4 allows remote attackers with a valid tls-crypt-v2 client key to potentially cause a denial of service
Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer.
OpenVPN Access Server 2.9.0 through 2.9.4 allow remote attackers to inject arbitrary web script or HTML via the web login page URL.
OpenVPN Connect 3.2.0 through 3.3.0 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 (OpenVPNConnect.exe).
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).
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.