libssh2: integer overflow (CVE-2019-17498)
An integer overflow vulnerability exists in libssh2 version 1.9.0 and earlier.
The vulnerability is an out-of-bounds read, potentially leading to either denial of service or remote information disclosure. It is triggered when libssh2 is used to connect to a malicious SSH server. The overflow occurs when the SSH server sends a disconnect message, which means that the vulnerability can be triggered early in the connection process, before authentication is completed.
References
https://blog.semmle.com/libssh2-integer-overflow-CVE-2019-17498/
Patch
https://github.com/libssh2/libssh2/pull/402/commits/1c6fa92b77e34d089493fe6d3e2c6c8775858b94