Software Engineering Institute

CoreFTP is susceptible to a buffer overflow when parsing long directory names from a malicious FTP server. The LIST, VIEW, commands are vulnerable to a denial of service and the DELE command has been reported to be vulnerable to code execution.

A user that is tricked into visiting a malicious FTP server and deleting a directory with a long name may allow arbitrary code to run on the user's computer.

Apply an Update

Upgrade to CoreFTP 2.2 build 1769 or later. If you are unable to upgrade, please consider the following workarounds.

Use the Microsoft Enhanced Mitigation Experience Toolkit

The Microsoft Enhanced Mitigation Experience Toolkit (EMET) can be used to help prevent exploitation of this vulnerability. CERT/CC has created a video tutorial for setting up EMET 3.0 on Windows 7. Note that platforms that do not support ASLR, such as Windows XP and Windows Server 2003, will not receive the same level of protection that modern Windows platforms will.

Enable DEP in Microsoft Windows

Consider enabling Data Execution Prevention (DEP) in supported versions of Windows. DEP should not be treated as a complete workaround, but it can mitigate the execution of attacker-supplied code in some cases. Microsoft has published detailed technical information about DEP in Security Research & Defense blog posts "Understanding DEP as a mitigation technology" part 1 and part 2. DEP should be used in conjunction with the application of patches or other mitigations described in this document.

Note that when relying on DEP for exploit mitigation, it is important to use a system that supports Address Space Layout Randomization (ASLR) as well. ASLR is not supported by Windows XP or Windows Server 2003 or earlier. ASLR was introduced with Microsoft Windows Vista and Windows Server 2008. Please see the Microsoft SRD blog entry: On the effectiveness of DEP and ASLR for more details.