SECURITY UPDATE: double free in sftp_open() lets a malicious SSH server
corrupt the heap of an authenticated client opening an SFTP session
debian/patches/CVE-2026-66032.patch: set data to NULL after freeing the
SSH_FXP_STATUS response buffer on the FX_OK path, so the if(badness)
arm cannot free the same pointer a second time when the follow-up
sftp_packet_require() for SSH_FXP_HANDLE fails, in sftp_open() in
src/sftp.c