Priority LOW 36
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 w…
CVSS 4.0HIGH 7.7· Network · No auth · User interaction · EPSS 0.00472 · Published 2026-07-24 · Partial fix CWE-122
Priority LOW 36
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 poin…
CVSS 4.0HIGH 7.7· Network · No auth · User interaction · EPSS 0.00402 · Published 2026-07-24 · Partial fix CWE-125
Priority MEDIUM 44
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 connecti…
CVSS 4.0HIGH 8.7· Network · No auth · No interaction · EPSS 0.00583 · Published 2026-07-24 · Partial fix CWE-125
Priority MEDIUM 40
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 a…
CVSS 4.0HIGH 8.7· Network · No auth · User interaction · EPSS 0.00448 · Published 2026-07-24 · Partial fix CWE-415
Priority HIGH 69
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 op…
CVSS 4.0HIGH 8.3· Network · No auth · No interaction · EPSS 0.00277 · Published 2026-06-28 · Partial fix CWE-908
Priority LOW 36
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…
CVSS 4.0HIGH 8.3· Network · No auth · No interaction · EPSS 0.00444 · Published 2026-06-28 · Partial fix CWE-190
Priority LOW 37
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…
CVSS 4.0HIGH 8.3· Network · No auth · No interaction · EPSS 0.00648 · Published 2026-06-18 · Partial fix CWE-125
Priority HIGH 75
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.
CVSS 4.0CRITICAL 9.2· Network · No auth · No interaction · EPSS 0.03877 · Published 2026-06-17 · Partial fix CWE-680
Priority LOW 37
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 exha…
CVSS 4.0HIGH 8.2· Network · No auth · No interaction · EPSS 0.00918 · Published 2026-06-17 · Partial fix CWE-835
Priority HIGH 70
A security vulnerability has been detected in libssh2 up to 1.11.1.
CVSS 4.0MEDIUM 6.9· Network · No auth · No interaction · EPSS 0.00466 · Published 2026-05-01 · Partial fix CWE-189
Priority HIGH 70
The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negoti…
CVSS 3.1MEDIUM 5.9· Network · No auth · No interaction · EPSS 0.93547 · Published 2023-12-18 · Partial fix · 0.40.2, 0.17.0 +2 CWE-354
Priority MEDIUM 41
An issue was discovered in function _libssh2_packet_add in libssh2 1.10.0 allows attackers to access out of bounds memory.
CVSS 3.1HIGH 7.5· Network · No auth · No interaction · EPSS 0.01155 · Published 2023-08-22 · Partial fix CWE-787
Priority MEDIUM 42
In libssh2 v1.9.0 and earlier versions, the SSH_MSG_DISCONNECT logic in packet.c has an integer overflow in a bounds check, enabling an attacker to specify an arbitrary (out-of-bounds) offset for a subsequent memory read…
CVSS 3.1HIGH 8.1· Network · No auth · User interaction · EPSS 0.03807 · Published 2019-10-21 · Partial fix CWE-190
Priority MEDIUM 49
In libssh2 before 1.9.0, kex_method_diffie_hellman_group_exchange_sha256_key_exchange in kex.c has an integer overflow that could lead to an out-of-bounds read in the way packets are read from the server.
CVSS 3.1HIGH 8.1· Network · No auth · User interaction · EPSS 0.11659 · Published 2019-07-16 · Will not fix CWE-125
Priority MEDIUM 49
An integer overflow flaw, which could lead to an out of bounds write, was discovered in libssh2 before 1.8.1 in the way keyboard prompt requests are parsed.
CVSS 3.1HIGH 8.8· Network · No auth · User interaction · EPSS 0.06131 · Published 2019-03-25 · Partial fix CWE-190
Priority MEDIUM 49
An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way SSH_MSG_CHANNEL_REQUEST packets with an exit signal are parsed.
CVSS 3.1HIGH 8.8· Network · No auth · User interaction · EPSS 0.06131 · Published 2019-03-25 · Partial fix CWE-190
Priority MEDIUM 48
An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the way SFTP packets with empty payloads are parsed.
CVSS 3.0CRITICAL 9.1· Network · No auth · No interaction · EPSS 0.05424 · Published 2019-03-25 · Will not fix CWE-125
Priority MEDIUM 47
An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the way SSH packets with a padding length value greater than the packet length are parsed.
CVSS 3.0CRITICAL 9.1· Network · No auth · No interaction · EPSS 0.05118 · Published 2019-03-25 · Partial fix CWE-125
Priority MEDIUM 46
A flaw was found in libssh2 before 1.8.1 creating a vulnerability on the SSH client side.
CVSS 3.0HIGH 8.8· Network · No auth · User interaction · EPSS 0.03437 · Published 2019-03-25 · Partial fix CWE-190
Priority MEDIUM 49
An out of bounds read flaw was discovered in libssh2 before 1.8.1 when a specially crafted SFTP packet is received from the server.
CVSS 3.0CRITICAL 9.1· Network · No auth · No interaction · EPSS 0.06448 · Published 2019-03-21 · Partial fix CWE-125
Priority MEDIUM 52
An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way packets are read from the server.
CVSS 3.1HIGH 8.8· Network · No auth · User interaction · EPSS 0.09294 · Published 2019-03-21 · Partial fix CWE-190
Priority MEDIUM 50
An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the way SSH_MSG_CHANNEL_REQUEST packets with an exit status message and no payload are parsed.
CVSS 3.0CRITICAL 9.1· Network · No auth · No interaction · EPSS 0.07898 · Published 2019-03-20 · Partial fix CWE-130
Priority MEDIUM 54
An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and _libssh2_packet_requirev functions.
CVSS 3.1CRITICAL 9.1· Network · No auth · No interaction · EPSS 0.06275 · Published 2019-03-20 · Will not fix CWE-125
Priority LOW 31
The diffie_hellman_sha256 function in kex.c in libssh2 before 1.7.0 improperly truncates secrets to 128 or 256 bits, which makes it easier for man-in-the-middle attackers to decrypt or intercept SSH sessions via unspecif…
CVSS 3.0MEDIUM 5.9· Network · No auth · No interaction · EPSS 0.02591 · Published 2016-04-13 · Fixed CWE-200
Priority LOW 36
The kex_agree_methods function in libssh2 before 1.5.0 allows remote servers to cause a denial of service (crash) or have other unspecified impact via crafted length values in an SSH_MSG_KEXINIT packet.
CVSS 2.0MEDIUM 6.8· Network · No auth · Interaction — · EPSS 0.03501 · Published 2015-03-13 · Partial fix CWE-20