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
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.
Mistress Ezada Sinn - Wide Open For My Huge Coc... Here
The traveler, touched by her warmth, began to share tales of his adventures across the lands. With each story, Mistress Ezada Sinn's eyes sparkled, and her laughter echoed through the forest, making the trees sway gently in delight.
Mistress Ezada Sinn was known far and wide for her vast, open heart and her home that was literally as wide open as the horizon. Her abode was not confined by walls or fences; it was a realm where the sky met the earth, and where every creature, no matter how big or small, was welcomed. Mistress Ezada Sinn - Wide open for My huge coc...
And so, Mistress Ezada Sinn's realm remained wide open, not just in physical space but in spirit, welcoming all who sought connection, understanding, and the sharing of stories. The traveler, touched by her warmth, began to
One day, a traveler with a huge coc - a basket filled with the most exotic and rare goods from distant lands - stumbled upon Mistress Ezada Sinn's open realm. The traveler, intrigued by the openness and the tranquility that filled the air, decided to introduce himself and his goods to Mistress Ezada. Her abode was not confined by walls or
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.