Will Cosgrove

4 exploits Active since Oct 2019
CVE-2025-15661 WRITEUP MEDIUM WRITEUP
libssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.c
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.
CVSS 6.5
CVE-2026-55200 WRITEUP HIGH WRITEUP
libssh2 - Out-of-Bounds Write via Unchecked packet_length in transport.c
libssh2 through 1.11.1, fixed in commit 7acf3df 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.
CVSS 8.1
CVE-2019-17498 WRITEUP HIGH WRITEUP
libssh2 < 1.9.0 - Integer Overflow in SSH_MSG_DISCONNECT Bounds Check
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. A crafted SSH server may be able to disclose sensitive information or cause a denial of service condition on the client system when a user connects to the server.
CVSS 8.1
CVE-2026-7598 WRITEUP HIGH WRITEUP
libssh2 userauth.c userauth_password integer overflow
A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauth_password of the file src/userauth.c. Such manipulation of the argument username_len/password_len leads to integer overflow. The attack may be launched remotely. The name of the patch is 256d04b60d80bf1190e96b0ad1e91b2174d744b1. A patch should be applied to remediate this issue.
CVSS 7.3