<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> /* *\ / * * \ / * * \ / * * \ / * System Vulnerabilities * \ | * * | | * * | | * * | | * Another Modernz Presentation * | | * * | \ * by * / \ * Multiphage * / \ * * / \ * (C)opyright August 5th, 1992 * / \ * */ ********************************************************* <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> ******************************************************************************* The Modernz can be contacted at: MATRIX BBS WOK-NOW! World of Kaos NOW! World of Knowledge NOW! St. Dismis Institute - Sysops: Wintermute Digital-demon (908) 905-6691 (908) WOK-NOW! (908) 458-xxxx 1200/2400/4800/9600 14400/19200/38400 Home of Modernz Text Philez <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>< <*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*> <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> TANSTAAFL Pheonix Modernz The Church of Rodney - Sysop: Tal Meta (908) 830-TANJ (908) 830-8265 Home of TANJ Text Philez <*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*> CyberChat Sysop: Hegz (908)506-6651 (908)506-7637 300/1200/2400/4800/9600 14400/19200/38400 Modernz Site TLS HQ <><><><><><><><><><><><><><<><<><><><><><><><><><><><><><><><><><><><><><><><>< The Global Intelligence Center World UASI Headquarters! Pennsylvania SANsite! (412) 475-4969 300/1200/2400/9600 24 Hours! SysOp: The Road Warrior <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>< The Lost Realm Western PA UASI site! Western PA. SANfranchise (412) 588-5056 300/1200/2400 SysOp: Orion Buster <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>< The Last Outpost PowerBBS Support Board UASI ALPHA Division NorthWestern PA UASI site! (412) 662-0769 300/1200/2400 24 hours! SysOp: The Almighty Kilroy <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>< Hellfire BBS SANctuary World Headquarters! New Jersey UASI site! (908) 495-3926 300/1200/2400 24 hours! SysOp: Red <*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*> BlitzKreig BBS Home of TAP (502)499-8933 <*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*><*> =========================================================================== AT&T /usr/etc/rexecd Vulnerability --------------------------------------------------------------------------- Information concerning a vulnerability in AT&T TCP/IP Release 4.0 running on SVR4 systems for both the 386/486 and 3B2 RISC platforms. The existing error, in the remote execution server /usr/etc/rexecd, has been corrected, and a new executable for rexecd is available from AT&T by calling 800-543-9935. Patches may be obtained outside the U.S. by calling your local technical support. The numbers associated with the fix are 5127 (3.5" media) and 5128 (5.25" media). The problem does not exist in TCP/IP release 3.2 for SVR3, or any earlier versions of the TCP/IP product running on either the 3B2 or 386 platforms. The version of TCP/IP distributed with SVR4 by UNIX(r) System Laboratories, Inc. (a subsidiary of AT&T) does not contain this vulnerability. UNIX(r) is a registered trademark of UNIX System Laboratories, Inc. --------------------------------------------------------------------------- I. Description A vulnerability has been identified where root privileges may be accessed through the use of /usr/etc/rexecd. II. Impact A user on a remote machine may be able to run commands as root on the target host (the host running the affected /usr/etc/rexecd). III. Solution 1. Administrators of affected systems should execute, as root, the following command to immediately turn off access to rexecd until the new binary can be obtained. # chmod 400 /usr/etc/rexecd 2. Obtain and install the new patch. The fix will be supplied as one diskette, and it comes with one page of instructions documenting the procedure to replace the existing /usr/etc/rexecd binary. --------------------------------------------------------------------------- AIX REXD Daemon Vulnerability --------------------------------------------------------------------------- Information concerning a vulnerability with the rexd daemon in versions 3.1 and 3.2 of AIX for IBM RS/6000 machines. IBM is aware of the problem and it will be fixed in future updates to AIX 3.1 and 3.2. Sites may call IBM Support (800-237-5511) and ask for the patch for apar ix21353. Patches may be obtained outside the U.S. by contacting your local IBM representative. The fix is also provided below. --------------------------------------------------------------------------- I. Description In certain configurations, particularly if NFS is installed, the rexd (RPC remote program execution) daemon is enabled. Note: Installing NFS with the current versions of "mknfs" will re-enable rexd even if it was previously disabled. II. Impact If a system allows rexd connections, anyone on the Internet can gain access to the system as a user other than root. III. Solution CERT/CC and IBM recommend that sites take the following actions immediately. These steps should also be taken whenever "mknfs" is run. 1. Be sure the rexd line in /etc/inetd.conf is commented out by having a '#' at the beginning of the line: #rexd sunrpc_tcp tcp wait root /usr/etc/rpc.rexd rexd 100017 1 2. Refresh inetd by running the following command as root: refresh -s inetd