These pages are published after PatchSiren validates generated defensive summaries against stored public CVE and source evidence.
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 [truncated]
CVE-2025-15661 is a high-severity vulnerability in libssh2, a popular SSH library. An out-of-bounds heap read vulnerability exists in the sftp_symlink() function, allowing a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash. The vulnerability is triggered by a crafted SSH_FXP_NAME response, which can be sent during SFTP READLINK and REALPATH operations. A [truncated]
libssh2 through 1.11.1 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. This vulnerability is particularly concerning for systems and applications that use libssh2 for SSH functionality, as an attacker could explo [truncated]
CVE-2026-55199 is a high-severity pre-authentication denial of service vulnerability in libssh2, allowing a malicious SSH server to cause a client CPU exhaustion loop. The vulnerability is triggered by a crafted extension count value in the SSH_MSG_EXT_INFO handler. 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 second [truncated]
CVE-2026-7598 is an integer overflow vulnerability in the userauth_password function of libssh2, a popular SSH library. The vulnerability is caused by improper handling of the username_len and password_len arguments, which can lead to an integer overflow. This vulnerability can be exploited remotely, and its successful exploitation can lead to potential security risks. The Common Vulnerability Scoring Sys [truncated]