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Recherche « Libssh libssh »

24 CVE

Critique 0 Élevée 13 Moyenne 8 Faible 1 Non évaluée 2 Exploitées (KEV) Tri : plus récentes « Libssh libssh » ✕
  1. CVE-2026-94423 – Non évaluée

    Net::LibSSH versions before 0.004 for Perl authenticate to an unverified server because connect never checks the host key against known_hosts. connect reports success as soon as ssh_connect returns SSH_OK. libssh leaves the known-hosts check to the application, and this binding never makes it, so the strict_hostkeycheck and knownhosts options are set on the session and then decide nothing. Password, agent and public-key authentication, channel and SFTP operations all run on a session whose peer was never identified, so an attacker who can redirect the connection receives the password when password authentication is used, and commands and data sent over the session.

  2. CVE-2026-87865 – Non évaluée

    curl

    When libcurl uses libssh2 with a hashed `known_hosts` file, an unrelated initial entry can cause host key validation to report a key *mismatch* as a *missing* key to the `CURLOPT_SSH_KEYFUNCTION` callback.

  3. CVE-2026-107675 5.9 Moyenne

    FFmpeg · Ffmpeg ffmpeg

    FFmpeg through 9.0.2 contains a missing host key verification vulnerability in the libssh-based sftp protocol handler that allows network attackers to impersonate SFTP servers. Attackers performing man-in-the-middle, DNS, or ARP spoofing can capture passwords supplied in sftp URLs, serve forged media, or receive uploaded output.

  4. CVE-2026-5917 8.8 Élevée

    libgit2

    libgit2 versions before 1.8.7 and 1.9.0 before 1.9.7 built with the libssh2 SSH backend (USE_SSH=libssh2) contain a shell command injection vulnerability that allows remote attackers to execute arbitrary commands on an SSH server by supplying a repository path containing unescaped shell metacharacters such as single quotes, semicolons, or pipes. The gen_proto() function in ssh_libssh2.c inserts the repository path directly into a shell command string without escaping special characters before passing it to libssh2_channel_exec(), enabling an attacker to craft a malicious submodule URL in a .gitmodules file that, when processed during a recursive clone, causes the remote server's shell to interpret injected commands under the victim's SSH user account.

  5. CVE-2026-66035 7.5 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packet_length smaller than the cipher's block size during Encrypt-then-MAC cipher negotiation. In the fullpacket() function in src/transport.c, the ETM path allocates a buffer of packet_length bytes but copies blocksize minus one bytes via memcpy, causing an overflow that on 32-bit glibc writes attacker-controlled bytes into an adjacent chunk's SIZE field, enabling tcache bin confusion, overlapping live objects, and function pointer overwrite during the session handshake before authentication.

  6. CVE-2026-66034 7.5 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2_publickey_list_fetch(), the version 1 response parser reads a server-controlled comment_len value and advances the parse pointer without verifying sufficient bytes remain in the buffer, causing the out-of-bounds read to leak heap pointers from adjacent allocations defeating ASLR, followed by heap allocator state corruption when the error cleanup path frees an uninitialized pointer from a non-zeroed realloc() region.

  7. CVE-2026-66033 7.5 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2_cipher_crypt() function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit the underflow in the expression computing blocksize minus aadlen minus authentication tag length to trigger an out-of-bounds read and a memcpy call with a near-SIZE_MAX length argument, causing immediate process crash before any authentication occurs.

  8. CVE-2026-66032 8.8 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1, fixed in commit 5e47761, contains a double-free vulnerability in the sftp_open() function in src/sftp.c that allows a malicious SSH server to corrupt the heap of any authenticated client opening an SFTP session. When a server responds to SSH_FXP_OPEN with SSH_FXP_STATUS containing FX_OK, the response data buffer is freed, and if a subsequent sftp_packet_require() call returns a specific error such as LIBSSH2_ERROR_CHANNEL_PACKET_EXCEEDED, the same pointer is freed a second time, enabling tcache dup conditions on glibc systems that allow overlapping allocations and function pointer overwrites.

  9. CVE-2026-59851 8.8 Élevée

    Red Hat Enterprise Linux 10 · Red Hat Hardened Images · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9

    A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users.

  10. CVE-2026-59850 7.5 Élevée

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. If data packets are processed after a channel is closed, channel data callbacks can be invoked after the associated data has already been freed, leading to crashes or possible use-after-free conditions.

  11. CVE-2026-59849 7.5 Élevée

    Red Hat Enterprise Linux 10 · Red Hat Hardened Images · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9

    A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service.

  12. CVE-2026-59848 5.3 Moyenne

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. A malicious SFTP server can send responses for unknown request IDs that libssh clients keep queued indefinitely, causing unbounded memory growth and client-side denial of service.

  13. CVE-2026-59847 7.5 Élevée

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. Incorrect AES-GCM finalization checks in builds using the OpenSSL backend can effectively remove integrity protection, allowing an in-path attacker to modify plaintext on the wire without detection.

  14. CVE-2026-59846 3.9 Faible

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. A malicious username expanded through %r in ProxyCommand handling can inject shell metacharacters, exposing environment variables and causing unintended shell behavior.

  15. CVE-2026-59845 5.9 Moyenne

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. When ProxyCommand is used, an unchecked fork() failure can be stored as process ID -1; during cleanup, signals may then be sent across the caller's accessible process tree, leading to local denial of service.

  16. CVE-2026-59844 6.5 Moyenne

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. A remote authenticated client can issue SSH_FXP_READ requests with an arbitrarily large length, causing a libssh SFTP server to allocate excessive memory and potentially exhaust it through repeated requests.

  17. CVE-2026-59843 6.5 Moyenne

    Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Hardened Images

    A flaw was found in libssh. A remote authenticated peer can advertise a zero maximum packet size in SSH_MSG_CHANNEL_OPEN, causing later channel writes to loop indefinitely and consume CPU, leading to denial of service.

  18. CVE-2026-59842 5.3 Moyenne

    Red Hat Enterprise Linux 10 · Red Hat Hardened Images · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9

    A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.

  19. CVE-2026-15370 7.3 Élevée

    Red Hat Enterprise Linux 10 · Red Hat Hardened Images · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9

    A flaw was found in libssh. During SFTP server directory listing, the longname field is constructed with unsafe concatenation into a fixed-size stack buffer. When a client causes the server to list attacker-controlled filenames, sufficiently long names can overflow that stack buffer and may lead to crashes or possible code execution on the server.

  20. CVE-2026-58051 6.5 Moyenne

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1 grows its publickey list with SSH2_REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2_publickey_list_free operating on an uninitialized entry. A malicious SSH server offering the publickey subsystem can use a malformed response to make cleanup free an uninitialized, attacker-influenceable attrs pointer in a connecting libssh2 client.

  21. CVE-2026-58050 7.5 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation num_attrs * sizeof(libssh2_publickey_attribute) without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious SSH server can then drive the attribute-parsing loop to write past the allocation, causing a heap buffer overflow in a connecting libssh2 client.

  22. CVE-2025-15661 6.5 Moyenne

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.

  23. CVE-2026-55200 8.3 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 1.11.1, fixed in commit 97acf3d, contains an out-of-bounds write vulnerability in ssh2_transport_read() that fails to enforce upper bounds on packet_length field. Remote attackers can send crafted SSH packets with excessively large packet_length values to corrupt heap memory and achieve remote code execution.

  24. CVE-2026-55199 7.5 Élevée

    libssh2 · Libssh2 libssh2

    libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSH_MSG_EXT_INFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can set nr_extensions to 0xFFFFFFFF during key exchange, causing the client to spin in a tight CPU loop for over 60 seconds because return values from _libssh2_get_string() are unchecked and the session timeout does not apply to CPU-bound loops.