CVE-2011-1137: Integer overflow in the mod_sftp (aka SFTP) module in ProFTPD 1.3.3d and earlier allows remote attackers to...

Security readout for executives and security teams

CVE-2011-1137 is a denial-of-service flaw in ProFTPD's mod_sftp component. A malformed SSH message can trigger excessive memory consumption, potentially causing the service or host to be killed by the operating system. The sources identify ProFTPD 1.3.3d and earlier as affected. Exposure is most likely on systems running ProFTPD 1.3.3d or earlier with mod_sftp enabled and reachable over SSH/SFTP from untrusted networks. Treat this as a service-availability risk for legacy SFTP infrastructure. Prioritize internet-facing ProFTPD servers and systems supporting business-critical file transfer workflows. Mitigation focus: Upgrade ProFTPD using the relevant vendor or distribution advisory package.; Confirm deployed ProFTPD is newer than 1.3.3d or contains the vendor backport.; Follow ProFTPD and OS vendor guidance for mod_sftp-specific remediation..

Prepared

Jun 24, 2026, 13:28 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.