diffutils, a set of utilities distributed with many versions of linux, contains a utility called sdiff, which creates temporary files of predictable names in an insecure fashion. Using a symbolic link attack, an intruder can cause overwrite of any file writable by the user executing sdiff.
sdiff creates temporary files as part of the file comparison process. Under some conditions, sdiff will create files in /tmp with predictable names, and furthermore does not check for prior existence or ownership of these files.
By creating a series of symbolic links, an intruder can cause sdiff to overwrite any file writable by the user executing sdiff, which may corrupt data or deny service.
Apply vendor patches; see the Systems Affected section below.
This vulnerability was first described by Greg Kroah-Hartman of Immunix.
This document was last modified by Tim Shimeall.
|Date First Published:||2001-10-09|
|Date Last Updated:||2001-11-08 18:26 UTC|