Veille CVE

Mai 2026

9 CVE

  1. CVE-2026-45918 5.5 Moyenne

    Linux · Linux linux kernel

    In the Linux kernel, the following vulnerability has been resolved: ovpn: tcp - don't deref NULL sk_socket member after tcp_close() When deleting a peer in case of keepalive expiration, the peer is removed from the OpenVPN hashtable and is temporary inserted in a "release list" for further processing. This happens in: ovpn_peer_keepalive_work() unlock_ovpn(release_list) This processing includes detaching from the socket being used to talk to this peer, by restoring its original proto and socket ops/callbacks. In case of TCP it may happen that, while the peer is sitting in the release list, userspace decides to close the socket. This will result in a concurrent execution of: tcp_close(sk) __tcp_close(sk) sock_orphan(sk) sk_set_socket(sk, NULL) The last function call will set sk->sk_socket to NULL. When the releasing routine is resumed, ovpn_tcp_socket_detach() will attempt to dereference sk->sk_socket to restore its original ops member. This operation will crash due to sk->sk_socket being NULL. Fix this race condition by testing-and-accessing sk->sk_socket atomically under sk->sk_callback_lock.

  2. CVE-2026-9560 7.8 Élevée

    OpenVPN Inc OpenVPN Connect · Openvpn connect

    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

  3. CVE-2026-9456 9.8 Critique

    Totolink A8000RU

    A vulnerability was found in Totolink A8000RU 7.1cu.643_b20200521. Impacted is the function setOpenVpnCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. The manipulation of the argument enabled results in os command injection. The attack can be executed remotely. The exploit has been made public and could be used.

  4. CVE-2026-9455 9.8 Critique

    Totolink A8000RU

    A vulnerability has been found in Totolink A8000RU 7.1cu.643_b20200521. This issue affects the function UploadOpenVpnCert of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. The manipulation of the argument FileName leads to os command injection. Remote exploitation of the attack is possible. The exploit has been disclosed to the public and may be used.

  5. CVE-2026-9454 9.8 Critique

    Totolink A8000RU

    A flaw has been found in Totolink A8000RU 7.1cu.643_b20200521. This vulnerability affects the function setOpenVpnCertGenerationCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Executing a manipulation of the argument servername can lead to os command injection. The attack may be launched remotely. The exploit has been published and may be used.

  6. CVE-2026-41070 10.0 Critique

    jkroepke openvpn-auth-oauth2

    openvpn-auth-oauth2 is a plugin/management interface client for OpenVPN server to handle an OIDC based single sign-on (SSO) auth flows. From version 1.26.3 to before version 1.27.3, when openvpn-auth-oauth2 is deployed in the experimental plugin mode (shared library loaded by OpenVPN via the plugin directive), clients that do not support WebAuth/SSO (e.g., the openvpn CLI on Linux) are incorrectly admitted to the VPN despite being denied by the authentication logic. The default management-interface mode is not affected because it does not use the OpenVPN plugin return-code mechanism. This issue has been patched in version 1.27.3.

  7. CVE-2026-43254 7.5 Élevée

    Linux · Linux linux kernel

    In the Linux kernel, the following vulnerability has been resolved: ovpn: tcp - fix packet extraction from stream When processing TCP stream data in ovpn_tcp_recv, we receive large cloned skbs from __strp_rcv that may contain multiple coalesced packets. The current implementation has two bugs: 1. Header offset overflow: Using pskb_pull with large offsets on coalesced skbs causes skb->data - skb->head to exceed the u16 storage of skb->network_header. This causes skb_reset_network_header to fail on the inner decapsulated packet, resulting in packet drops. 2. Unaligned protocol headers: Extracting packets from arbitrary positions within the coalesced TCP stream provides no alignment guarantees for the packet data causing performance penalties on architectures without efficient unaligned access. Additionally, openvpn's 2-byte length prefix on TCP packets causes the subsequent 4-byte opcode and packet ID fields to be inherently misaligned. Fix both issues by allocating a new skb for each openvpn packet and using skb_copy_bits to extract only the packet content into the new buffer, skipping the 2-byte length prefix. Also, check the length before invoking the function that performs the allocation to avoid creating an invalid skb. If the packet has to be forwarded to userspace the 2-byte prefix can be pushed to the head safely, without misalignment. As a side effect, this approach also avoids the expensive linearization that pskb_pull triggers on cloned skbs with page fragments. In testing, this resulted in TCP throughput improvements of up to 74%.

  8. CVE-2026-31893 5.5 Moyenne

    Tunnelblick · Tunnelblick tunnelblick

    Tunnelblick is an open source graphic user interface for OpenVPN on macOS. In versions 3.3beta26 through 9.0beta01, any local user can read arbitrary root-owned files by exploiting a symlink following vulnerability in tunnelblick-helper, reachable through the world-accessible tunnelblickd Unix socket. The socket is configured with mode 0666, allowing any local user to connect. No authorization check is performed on the connecting client. The tunnelblick-helper process constructs a path to config.ovpn inside a user-controlled .tblk directory and reads it as root without symlink validation. An attacker can create a .tblk configuration with a symlinked config.ovpn pointing to any file and request tunnelblickd to read it. This issue has been fixed in versions 9.0beta02.

  9. CVE-2025-42611 6.5 Moyenne

    Mikrotik RouterOS

    RouterOS provides various services that rely on correct verification of client and server certificates to secure confidentiality and integrity of communications. This includes OpenVPN, CAPsMAN, Dot1x (802.1X), among others. The vulnerability lies in shared certificate validation logic which uses the system certificate store that is shared and equally trusted by all system services. This causes confusion of scope, allowing any certificate authority present in the system-wide trust store to be trusted in any context (with some exceptions), allowing partial or full authentication bypass in CAPsMAN, OpenVPN, Dot1X and potentially others.