NGSSoftware Insight Security Research Advisory Name: Oracle RDBMS Data packet DoS Systems Affected: Oracle 8.1.7.4, 10g Release 2 and 1, Oracle 9 Severity: High Vendor URL: http://www.oracle.com/ Author: David Litchfield [ davidl (at) ngssoftware (dot) com [email concealed] ] Reported: 23rd June 2006 Date of Public Advisory: 17th October 2007 Advisory number: #NISR17102007D Description *********** The Oracle RDBMS on receiving an invalid TNS data packet will use 100% of the CPU's time introducing a Denial of Service condition. Details ******* Once a client connects to the database process and performs protocol negoation (TNS packet type 1) and data type represenations (packet type 2) it may then send packets of type 6 - Data packets. If the server gets a packet with the 2nd bit of the Data flags is set then the server runs at 100% CPU: "\x00\x1D" // Packet Size "\x00\x00" // Packet Checksum "\x06" // Packet Type [DATA] "\x00" // Flags "\x00\x00" // Header Checksum "\x00\x02" // Data flags "\x03\x3B" // TTI Version function .. .. The snippet of a packet above sets the Data flags to 0x0002 on a version request. This DoS condition can be triggered prior to authentication. This can be exploited by an unauthenticated attacker. Fix Information *************** Oracle was alerted to this flaw on the 23rd of June 2006. A patch has now been made available: http://www.oracle.com/technology/deploy/security/critical-patch-updates/ cpuo ct2007.html NGSSQuirreL for Oracle, an advanced vulnerability assessment scanner designed specifically for Oracle, can be used to accurately determine whether your servers is vulnerable to this flaw. More information about NGSSQuirreL for Oracle can be found here: http://www.ngssoftware.com/products/database-security/ngs-squirrel-oracl e.ph p About NGSSoftware ***************** NGSSoftware develops vulnerability assessment and compliancy tools for database servers including Oracle, Microsoft SQL Server, DB2, Sybase and Informix. Headquartered in the United Kingdom NGS has offices in London, St. Andrews (UK), Brisbane, and Perth (Australia) and seattle in the United States; NGSConsulting provide services to some of the largest and most demanding organizations around the globe. http://www.ngssoftware.com/ Telephone +44 208 401 0070 Fax +44 208 401 0076 enquiries (at) ngssoftware (dot) com [email concealed] -- E-MAIL DISCLAIMER The information contained in this email and any subsequent correspondence is private, is solely for the intended recipient(s) and may contain confidential or privileged information. For those other than the intended recipient(s), any disclosure, copying, distribution, or any other action taken, or omitted to be taken, in reliance on such information is prohibited and may be unlawful. If you are not the intended recipient and have received this message in error, please inform the sender and delete this mail and any attachments. The views expressed in this email do not necessarily reflect NGS policy. NGS accepts no liability or responsibility for any onward transmission or use of emails and attachments having left the NGS domain. NGS and NGSSoftware are trading names of Next Generation Security Software Ltd. Registered office address: 52 Throwley Way, Sutton, SM1 4BF with Company Number 04225835 and VAT Number 783096402