tnftp: Arbitrary file overwriting

Background

tnftp is a NetBSD FTP client with several advanced features.

Description

The ‘mget’ function in cmds.c lacks validation of the filenames that are supplied by the server.

Impact

An attacker running an FTP server could supply clients with malicious filenames, potentially allowing the overwriting of arbitrary files with the permission of the connected user.

Workaround

There is no known workaround at this time.

Resolution

All tnftp users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-ftp/tnftp-20050103"