Linux Distros Unpatched Vulnerability : CVE-2026-66033

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt function in src/openssl.c...

CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

DEBIAN-CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

UBUNTU-CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

CVE-2026-66033

CVE-2026-66033 affects libssh2 up to 1.11.1. A pre-authentication integer underflow in the ssh2_cipher_crypt() function (src/openssl.c) allows a malicious SSH server to crash a connecting client during handshake by negotiating AES-GCM ciphers. The underflow (blocksize − aadlen − taglen) can trigg...

CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

CVE-2026-66033 libssh2 Integer Underflow DoS via AES-GCM Cipher Negotiation

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

CVE-2026-66033 libssh2 Integer Underflow DoS via AES-GCM Cipher Negotiation

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

EUVD-2026-48720

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt 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...

PT-2026-64380

Name of the Vulnerable Software and Affected Versions libssh2 versions prior to 1.11.1 Description A pre-authentication integer underflow exists in the ssh2 cipher crypt function within src/openssl.c. A malicious SSH server can trigger this issue during the handshake by negotiating AES-GCM cipher...

libssh: libssh: integrity downgrade via OpenSSL AES-GCM tag verification

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...

CVE-2026-59847

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...

UBUNTU-CVE-2026-59847

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...

CVE-2026-59847

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...

EUVD-2026-46255

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...

CVE-2026-59847

CVE-2026-59847 affects the OpenSSH/libssh stack via an integrity downgrade caused by incorrect AES-GCM tag verification when using the OpenSSL backend. The provided connected documents indicate the issue in libssh before 0.11.5, with the vulnerability enabling an in-path attacker to compromise in...

CVE-2026-59847

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...

CVE-2026-59847 Libssh: libssh: integrity downgrade via openssl aes-gcm tag verification

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...