جزئیات آسیب‌پذیری

Xlight FTP Server before 3.9.5 contains a pre-authentication heap buffer overflow vulnerability that allows remote unauthenticated attackers to write past the end of a heap buffer by sending a malformed SSH client identification string. A logic error in the recv loop's termination condition uses an incorrect OR operator where an AND operator is required, enabling exploitation on any SSH or SFTP connection before authentication occurs.

• https://www.xlightftpd.com/whatsnew.htm release-notes
• https://www.vulncheck.com/advisories/xlight-ftp-server-pre-auth-heap-buffer-overflow-via-ssh-parser third-party-advisory