| vuln.sg Vulnerability Research Advisory |
by Tan Chew Keong 
Summary
A vulnerability has been found within the FTP client in AceFTP. When exploited, this vulnerability allows an anonymous attacker to write files to arbitrary locations on a Windows user's system.
Tested Versions
Details
This advisory discloses a vulnerability within the FTP client in AceFTP. When exploited, this vulnerability allows an anonymous attacker to write files to arbitrary locations on a Windows user's system. The FTP client does not properly sanitise filenames containing directory traversal sequences (forward-slash) that are received from an FTP server in response to the LIST command. An example of such a response from a malicious FTP server is shown below. Response to LIST (forward-slash): -rw-r--r-- 1 ftp ftp 20 Mar 01 05:37 /../../../../../../../../../testfile.txt\r\n By tricking a user to download a directory from a malicious FTP server that contains files with fowward-slash directory traversal sequences in their filenames, it is possible for the attacker to write files to arbitrary locations on a user's system with privileges of that user. An attacker can potentially leverage this issue to write files into a user's Windows Startup folder and execute arbitrary code when the user logs on.
POC / Test Code
Please download the POC here and follow the instructions below. Strive Conquest Itch High Quality NowA career pivot? A fitness PR? A creative block you’re determined to smash? Or are you finally learning to sit with the itch without scratching? I’ve started calling it the . Here’s a thought-provoking post written in the style of a personal blog or social media deep-dive (e.g., for LinkedIn, Medium, or a gaming/psychology forum). You can adapt the tone to fit your platform. The Strive Conquest Itch: Why We Grind, Climb, and Crave the Next Peak strive conquest itch It’s not ambition in the corporate sense. It’s not greed. It’s deeper than that. It’s the primal urge to prove capacity —to yourself, to the void, to the leaderboard. A career pivot Here’s what I’ve noticed about the itch: to the void
Avoid downloading files/directories from untrusted FTP servers.
Disclosure Timeline
2008-06-15 - Vulnerability Discovered. |
| Contact |
| For further enquries, comments, suggestions or bug reports, simply email them to |