Tcpdump version 3.5 contains a buffer overflow vulnerability permitting unauthorized remote root access.
Tcpdump version 3.5 added support for handling AFS packets. Unfortunately the code responsible for printing AFS access control lists contains an unchecked buffer that can be overflowed by a remote attacker by sending a crafted AFS packet into the target network. Any machine on the target network that is running tcpdump with a large (> ~500) snaplen argument when the hostile packet arrives can be made to execute arbitrary code. Since tcpdump requires root privileges in order to run, the arbitrary code will also run with root privileges. Fixed in version 3.6.1.
Note that a program that successfully exploits this vulnerability was publicly released on the BugTraq mailing list on January 11, 2001.
Attackers can remotely execute arbitrary code with root privileges on a vulnerable host.
Upgrade to version 3.6.1 or greater.
Filter incoming dst UDP 7000 packets from untrusted networks. Exclude dst UDP 7000 packets from tcpdump capture, e.g. "tcpdump not udp dst port 7000".
First public disclosure by email@example.com and the !Hispahack Research Team
|Date First Published:||2001-06-22|
|Date Last Updated:||2001-06-26 17:40 UTC|