Vulnerabilidades de libssh (CVE)

Registros CVE publicados para libssh, los más recientes primero. Siga el producto para recibir un correo con cada nueva.

26 resultados
8.8Alta
CVE-2026-59851

Libssh: libssh: authentication bypass via missing gssapi principal check

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Hardened Images; Red Hat Red Hat Enterprise Linux 8; Red Hat 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.

4.3Media
CVE-2026-59850

Libssh: libssh: use-after-free via data callbacks on closed channels

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 9; Red Hat 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.

3.1Baja
CVE-2026-59849

Libssh: libssh: denial of service via automatic certificate authentication loop

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Hardened Images; Red Hat Red Hat Enterprise Linux 8; Red Hat 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.

5.3Media
CVE-2026-59848

Libssh: libssh: denial of service via sftp responses with unknown request ids

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 9; Red Hat 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.

5.9Media
CVE-2026-59847

Libssh: libssh: integrity downgrade via openssl aes-gcm tag verification

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 9; Red Hat 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.

6.5Media
CVE-2026-59844

Libssh: libssh: denial of service via oversized sftp read length

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 9; Red Hat 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.

5.3Media
CVE-2026-59845

Libssh: libssh: denial of service via unchecked proxycommand fork() failure

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 9; Red Hat 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.

6.5Media
CVE-2026-59843

Libssh: libssh: denial of service via zero advertised channel packet size

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 9; Red Hat 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.

3.7Baja
CVE-2026-59842

Libssh: libssh: information disclosure via short gssapi curve25519 public key

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Hardened Images; Red Hat Red Hat Enterprise Linux 8; Red Hat 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 unauthent…

6.7Media
CVE-2026-15370

Libssh: libssh: stack buffer overflow in sftp server longname construction

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Hardened Images; Red Hat Red Hat Enterprise Linux 8; Red Hat 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 ov…

7.8Alta
CVE-2025-14821

Libssh: libssh: insecure default configuration leads to local man-in-the-middle attacks on windows

Red Hat Red Hat Hardened Images; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7

A flaw was found in libssh. This vulnerability allows local man-in-the-middle attacks, security downgrades of SSH (Secure Shell) connections, and manipulation of trusted host information, posing a significant risk to the confidentiality, integrity, and availa…

3.3Baja
CVE-2026-0965

Libssh: libssh: denial of service via improper configuration file handling

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7

A flaw was found in libssh where it can attempt to open arbitrary files during configuration parsing. A local attacker can exploit this by providing a malicious configuration file or when the system is misconfigured. This vulnerability could lead to a Denial …

2.2Baja
CVE-2026-0967

Libssh: libssh: denial of service via inefficient regular expression processing

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7

A flaw was found in libssh. A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the `match_pattern()` function can lead to inefficient regular expression backtracking. This c…

3.1Baja
CVE-2026-0968

Libssh: libssh: denial of service due to malformed sftp message

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7

A flaw was found in libssh in which a malicious SFTP (SSH File Transfer Protocol) server can exploit this by sending a malformed 'longname' field within an `SSH_FXP_NAME` message during a file listing operation. This missing null check can lead to reading bey…

6.5Media
CVE-2026-0966

Libssh: libssh: denial of service via zero-length input in ssh_get_hexa()

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Hardened Images; Red Hat Red Hat Enterprise Linux 6

A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authenti…

5.0Media
CVE-2026-0964

Libssh: improper sanitation of paths received from scp servers

Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7

A malicious SCP server can send unexpected paths that could make the client application override local files outside of working directory. This could be misused to create malicious executable or configuration files and make the user execute them under specifi…

6.5Media
CVE-2025-5449

Libssh: integer overflow in libssh sftp server packet length validation leading to denial of service

libssh; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7

A flaw was found in the SFTP server message decoding logic of libssh. The issue occurs due to an incorrect packet length check that allows an integer overflow when handling large payload sizes on 32-bit systems. This issue leads to failed memory allocation an…

1.0%EPSS
4.7Media
CVE-2025-8114

Libssh: null pointer dereference in libssh kex session id calculation

libssh; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 6

A flaw was found in libssh, a library that implements the SSH protocol. When calculating the session ID during the key exchange (KEX) process, an allocation failure in cryptographic functions may lead to a NULL pointer dereference. This issue can cause the cl…

8.1Alta
CVE-2025-5987

Libssh: invalid return code for chacha20 poly1305 with openssl backend

libssh; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support; Red Hat Red Hat Enterprise Linux 9

A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library. If an attacker manages to exhaust the heap space, this error is not detected and may lead to libssh using a partially initialized cipher context. This occurs because the OpenS…

1.7%EPSS
6.5Media
CVE-2025-5351

Libssh: double free vulnerability in libssh key export functions

libssh libssh; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 6

A flaw was found in the key export functionality of libssh. The issue occurs in the internal function responsible for converting cryptographic keys into serialized formats. During error handling, a memory structure is freed but not cleared, leading to a poten…

5.0Media
CVE-2025-5372

Libssh: incorrect return code handling in ssh_kdf() in libssh

libssh libssh; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support; Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

A flaw was found in libssh versions built with OpenSSL versions older than 3.0, specifically in the ssh_kdf() function responsible for key derivation. Due to inconsistent interpretation of return values where OpenSSL uses 0 to indicate failure and libssh uses…

5.4Media
CVE-2025-5318

Libssh: out-of-bounds read in sftp_handle()

libssh; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 8; Red Hat Red Hat Enterprise Linux 8.2 Advanced Update Support

A flaw was found in the libssh library in versions less than 0.11.2. An out-of-bounds read can be triggered in the sftp_handle function due to an incorrect comparison check that permits the function to access memory beyond the valid handle list and to return …

1.9%EPSS