vuln.sg Vulnerability Research Advisory

AceFTP FTP-Client Directory Traversal Vulnerability by Tan Chew Keong Release Date: 2008-06-27    [en] [jp] 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 AceFTP Freeware Version 3.80.3 AceFTP Pro Version 3.80.3 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. File: Tower.tactics.liberation.v1.0.zip ... Apr 2026 Tower Tactics: Liberation officially released its v1.0 update on February 7, 2023, transitioning out of early access with new features like the Overload system, Infinite Ascension, and Red Tiles. Developed by AsraWorks, the title combines tower defense with deck-building, featuring procedural progression, tower synergy, and full controller support. More information is available on the Tower Tactics: Liberation Wiki. Patch / Workaround Avoid downloading files/directories from untrusted FTP servers. Disclosure Timeline 2008-06-15 - Vulnerability Discovered. 2008-06-16 - Vulnerability Details Sent to Vendor via online support form (no reply). 2008-06-18 - Vulnerability Details Sent to Vendor again via online support form (no reply). 2008-06-25 - Vulnerability Details Sent to Vendor again via online support form (no reply). 2008-06-27 - Public Release.

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