Servers and applications
CVE-2011-1575 The STARTTLS implementation in ftp_parser.c in Pure-FTPd before 1.0.30 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted FTP sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.
Severity Medium 5.8
Published 23 May 2011
Last changed 16 Jun 2026
Added to UpHeron 1 Nov 2026 Exploit chance 33% in the next 30 daysHigher than 98% of CVEs. EPSS by FIRST , 12 Nov 2026
Attack Over the network · No login needed
Attacker can Read some data · Change some data
CVSS vector AV:N/AC:M/Au:N/C:P/I:P/A:N
Sources NVD Affected software Software Affected versions Pure-FTPdServers and applications · cpe:a:pureftpd:pure-ftpd Version 1.0.28 Version 1.0.27 Version 1.0.26 Version 1.0.25 All 87 release lines Every version up to 1.0.29 Version 0.90 Version 0.91 Version 0.92 Version 0.93 Version 0.94 Version 0.95-pre1 Version 0.95-pre2 Version 0.95-pre3 Version 0.95-pre4 Version 0.95 Version 0.95.1 Version 0.95.2 Version 0.96pre1 Version 0.96 Version 0.96.1 Version 0.97pre1 Version 0.97pre2 Version 0.97pre3 Version 0.97pre4 Version 0.97pre5 Version 0.97-final Version 0.97.1 Version 0.97.2 Version 0.97.3 Version 0.97.4 Version 0.97.5 Version 0.97.6 Version 0.97.7pre1 Version 0.97.7pre2 Version 0.97.7pre3 Version 0.97.7 Version 0.98pre1 Version 0.98pre2 Version 0.98-final Version 0.98.1 Version 0.98.2 Version 0.98.2a Version 0.98.3 Version 0.98.4 Version 0.98.5 Version 0.98.6 Version 0.98.7 Version 0.99pre1 Version 0.99pre2 Version 0.99 Version 0.99a Version 0.99b Version 0.99.1 Version 0.99.1a Version 0.99.1b Version 0.99.2 Version 0.99.2a Version 0.99.3 Version 0.99.4 Version 0.99.9 Version 1.0.0 Version 1.0.1 Version 1.0.2 Version 1.0.3 Version 1.0.4 Version 1.0.5 Version 1.0.6 Version 1.0.7 Version 1.0.8 Version 1.0.9 Version 1.0.10 Version 1.0.11 Version 1.0.12 Version 1.0.13a Version 1.0.14 Version 1.0.15 Version 1.0.16a Version 1.0.16b Version 1.0.16c Version 1.0.17 Version 1.0.17a Version 1.0.18 Version 1.0.19 Version 1.0.20 Version 1.0.21 Version 1.0.22 Version 1.0.24 Version 1.0.25 Version 1.0.26 Version 1.0.27 Version 1.0.28
References NVD https://nvd.nist.gov/vuln/detail/CVE-2011-1575 CVE.org https://www.cve.org/CVERecord?id=CVE-2011-1575