CRITICALVulnerability
Verified
Global
NVD CRITICAL: CVE-2026-67191 — Xlight FTP Server before 3.9.5 contains a pre-authentication heap buffer overflo...
·Source: NIST NVD
Updated:
Executive Summary
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 co
Analysis
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. CVSS Score: 9.8. Published: 2026-07-29T16:17:57.540.