| 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. Pimsleur French Transcripts ^hot^How is the weather: Je ne comprends pas. (I don't understand.) Read the transcript aloud while listening to the audio. This helps connect the French sounds to their written forms, which is essential for literacy. pimsleur french transcripts Oui, je parle anglais. (Yes, I speak English.) (wee) Oui, j'ai entendu parler de ce film. J'ai voulu le voir, mais je n'ai pas eu le temps. How is the weather: Je ne comprends pas From a practical standpoint, accessing user-uploaded files carries risks. These files can sometimes contain malware, or you might inadvertently download an incomplete or inaccurate document. The safest and most ethical path is always to use the official course materials you have paid for. I have a few photos: (zhuh vay) Je vais faire des courses. J'ai besoin de acheter quelques choses.
Avoid downloading files/directories from untrusted FTP servers.
Disclosure Timeline
2008-06-15 - Vulnerability Discovered. |
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