DOS-Attack against Gauntlet Firewall ------------------------------------- We found out a security-issue with the Oracle-Proxy (SQL-Gateway) of Gauntlet Firewall, Version 6 (manufactured by Secure Computing/NAI, serversrunning Solaris 8, newest Patches installed). Abstract: --------- Sending subsequent requests with invalid data to the firewalls SQL-gateway results in an immediate crash. The firewall won't accept any further connections on any SQL-gw that is defined in the rule base. Secure Computing as vendor of Gauntlet could reproduce the DOS, patches or bug fixes are not yet available. Description: ------------- We tried to monitor the firewall's sql-gw with our own monitoring-system to make sure that we notice if it does not run. Some seconds later, the sql-gw crashed and we were no longer able to connect the port. Further investigation of the problem showed that the sql-gw-process can easily be crashed on any Gauntlet-Firewall by simply connecting to it: Try the following (_very_ basic)script, use your firewall's IP instead of aaa.bbb.ccc.ddd, running sql-gw at the standard port 1521: for a in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 do telnet aaa.bbb.ccc.ddd 1521 done You will see that the last try to connect (#17) results in "Connection refused" and the process of "sql-gw" is no longer running on the firewall. ==> A DOS against Gauntlet is very easy. This is especially unpleasant, as Gauntlet is one of the few major firewall-products that provide true application level security _and_ do have a dedicated application-proxy for SQL (sql-net 1 + 2). In fact, many companies use Gauntlet especially to protect database-servers. Solution/ Patches: ------------------ Secure Computing (www.securecomputing.com), the manufacturer of Gauntlet-Firewall, has been informed by arago about the issue in August 2003 and has been able to reproduce the problem. Unfortunately, they have not yet managed to bring out a security-patch :-( The only current solution they give is to use "plug-gws" instead of the "sql-gws", which obviously weakens security _and_ performance a lot, as you lose application-level security! Regards, Oliver Heinz --------------------------------------------------------------------- | arago, | Oliver Heinz | | Institut fuer komplexes | Bereichsleiter Systembetrieb & Security | | Datenmanagement AG | eMail: heinz@arago.de | | Am Niddatal 3 | | | 60488 Frankfurt am Main | http://www.arago.de/ | | | PGP-Fingerprint: a5de d4b4 46b3 4d8b 2646| | | d4d0 e5fd d842 cc4e 7315| ---------------------------------------------------------------------