NGSSoftware Insight Security Research Advisory Name: IBM DB2 libdb2.so.1 buffer overflow Systems Affected: DB2 8.1/7.x Severity: High risk from local Vendor URL: http://www.ibm.com/ Author: David Litchfield [ david at ngssoftware.com ] Relates to: http://www.nextgenss.com/advisories/db2-02.txt Date of Public Advisory: 5th January 2005 Advisory number: #NISR05012005B Advisory URL: http://www.ngssoftware.com/advisories/db205012005B.txt Description *********** libdb2.so.1, one of the libraries supplied with IBM's DB2 database server suffers from a buffer overflow vulnerability. Details ******* This vulnerability can be divided into two separate issues. Firstly, when libdb2.so is loaded it reads the DBLPORT environment variable and copies the value to a buffer in the .bss section. This buffer is overflowed. By providing an overly long DB2LPORT environment variable it fills the db2MLNPort_name buffer in the .bss section of libdb2.so.1 - then spills over into the db2node_name buffer, into the instprof_path buffer, into the instance_path buffer and so on all the way into the install_path buffer. Secondly, when the sqloInstancePath() reads the install_path we overflow a local stack based buffer of sqloGetInstancePath(). This can be exploited to gain root privileges. For example, db2cacpy is setuid root. This program loads the library and calls sqloInstancePath() overflowing the buffer. Fix Information *************** IBM has written a patch and can be obtained with the latest fixpak. http://www-306.ibm.com/software/data/db2/udb/support/downloadv8.html - DB2 v8.1 http://www-306.ibm.com/software/data/db2/udb/support/downloadv7.html - DB2 v7.x NGSSQuirreL for DB2 (http://www.nextgenss.com/db2.htm) can be used to assess whether your DB2 server is vulnerable to this. About NGSSoftware ***************** NGSSoftware design, research and develop intelligent, advanced application security assessment scanners. Based in the United Kingdom, NGSSoftware have offices in the South of London and the East Coast of Scotland. NGSSoftware's sister company NGSConsulting, offers best of breed security consulting services, specialising in application, host and network security assessments. http://www.ngssoftware.com/ Telephone +44 208 401 0070 Fax +44 208 401 0076 enquiries@ngssoftware.com