| 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. Qr Code Download Work ((better)): Servicenidwgov Bd NidpubWhile the web interface is straightforward, the Face Verification step is often cited by users as "troublesome" or technical. Once your environment is optimized, use this exact workflow to complete your download without triggers stalling: servicenidwgov bd nidpub qr code download work Where you input your NID number/Form number and date of birth. While the web interface is straightforward, the Face service.nidw.gov.bd Service: NID Card Copy Download via QR Code / NID Number While the web interface is straightforward : If scanning fails, a code can be copied from the browser and manually entered into the app. You will be asked to enter:
Avoid downloading files/directories from untrusted FTP servers.
Disclosure Timeline
2008-06-15 - Vulnerability Discovered. |
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