Donato Ferrante Application: Crackalaka http://www.stalphonsos.com/~attila/crackalaka Version: 1.0.8 Bug: Denial Of Service Date: 09-Apr-2004 Author: Donato Ferrante e-mail: fdonato@autistici.org web: www.autistici.org/fdonato xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 1. Description 2. The bug 3. The code 4. The fix xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ---------------- 1. Description: ---------------- Vendor's description: "Crackalaka is a small, standalone IRC server. It does not implement the inter-server portions of the IRC protocol, and is meant for use by a small workgroup, preferably behind a firewall." xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ------------ 2. The bug: ------------ The program is unable to manage a lot of not regular strings, in fact it crashes. The problem is in the function: hash_strcmp() of hash.c, in which the program try to manage an unallocated sector of memory. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ------------- 3. The code: ------------- To test the vulnerability try to send to the irc server some big and unregular strings or more simply you can use: nc [host] 6667 < /dev/urandom xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ------------ 4. The fix: ------------ Vendor was contacted. Bug will be probably fixed in the next version. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx