Vulnerability Note VU#685996
GNU Wget creates arbitrary symbolic links during recursive FTP download
Original Release date: 28 Oct 2014 | Last revised: 31 Oct 2014
GNU wget allows arbitrary filesystem access when creating symbolic links during a recursive FTP download. This allows an attacker to overwrite files with the permissions of the user running wget.
CWE-59: CWE-59: Improper Link Resolution Before File Access (‘Link Following’)
Wget is a common Unix utility to retrieve remote files. When wget is running in recursive mode (the -m or -r switch) with a FTP server as the destination, it is vulnerable to a link following attack. A malicious FTP server, when configured to provide symlinks in the directory listing, can force the client wget utility to enter into the the specified local symlink, navigating the local file system for the attacker. Wget will then download and create or overwrite existing files within the local symlink, setting permissions to those of the remote files.
See the Rapid7 advisory for more details.
A remote unauthenticated malicious FTP server, connected to the victim via wget, can create and overwrite arbitrary files in the context of the user running wget.
Apply an Update
This vulnerability is addressed in wget 1.16. Updates should also be available in various package formats for downstream Linux distributions. Check your distribution’s package management system for updates.
Enable wget symlink traversal
In wget versions 1.15 and earlier, configure retr-symlinks=on in /etc/wgetrc or ~/.wgetrc or specify –retr-symlinks as a command line option to wget.
Vendor Information (Learn More)
VendorStatusDate NotifiedDate UpdatedGNU wgetAffected-28 Oct 2014If you are a vendor and your product is affected, let
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Thanks to HD Moore and John Hart of Rapid7, Inc. for reporting this vulnerability.
This document was written by Chris King.
27 Oct 2014
Date First Published:
28 Oct 2014
Date Last Updated:
31 Oct 2014
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