Libssh: double free vulnerability in libssh key export functions

A flaw was found in the key export functionality of libssh. The issueoccurs in the internal function responsible for converting cryptographickeys into serialized formats. During error handling, a memory structure isfreed but not cleared, leading to a potential double free issue if anadditional failure occurs later in the function. This condition may resultin heap corruption or application instability in low-memory scenarios,posing a risk to system reliability where key export operations areperformed.

Where it's fixed