_____________________________________________________ The Computer Incident Advisory Capability ___ __ __ _ ___ / | / \ / \___ __|__ /___\ \___ _____________________________________________________ Information Bulletin Patch for TIOCCON in SunOS 4.1 and 4.1.1 Available December 21, 1990, 0900 PST Number B-10 ________________________________________________________________________ PROBLEM: Security problem in the TIOCCON redirection of console input/ output PLATFORM: Sun computer (all architectures) running SunOS versions 4.0.3 through 4.1.1 . DAMAGE: Allows misuse of the TIOCCON function PATCH: Available through anonymous ftp from ftp.uu.net or from Sun (contact Sun at 1-800-USA4SUN for details). A patch for SunOS 4.0.3 will be available soon. _______________________________________________________________________ Critical Facts about the TIOCCON patch CIAC has been informed of a problem with the TIOCCON function in SunOS 4.1 and 4.1.1. Sun Microsystems has developed a patch to close this vulnerability. The application of this patch should have no impact on current applications, i.e., should not cause existing systems to behave in an anomalous manner. The patch is available on the Internet using anonymous ftp to the site ftp.uu.net (ip address 192.48.96.2). Login with the username anonymous and use your account name as the password. The patches are in the directory ~ftp/sun-dist. The patch for systems running SunOS 4.1 and 4.1.1 is 100187-01.tar.Z and 100188-01.Z, respectively. If you do not have Internet access, you may request the patch from Sun or CIAC. Call 1-800-USA-4SUN and request patch 100187-01 for SunOS 4.1 and 100188-01 for SunOS 4.1.1. The patch file available on ftp.uu.net is a compressed tar archive of 5 object files that must be placed in the appropriate directory in /sys/sun?/OBJ, where sun? is one of sun4, sun4c, sun3, sun3x, or sun4/490-4.1_PSR_A. To install the patch, the files must be placed in this directory and a new kernel must be built. Once the kernel (file /vmunix) is replaced with the newly built version, the patch installation is complete. Appended to this notice is the original Sun Microsystems security bulletin concerning this vulnerability. Please contact CIAC for assistance. Thomas A. Longstaff (415) 423-4416 or (FTS) 543-4416 or call (415) 422-8193 or (FTS) 532-8193 Send FAX messages to: (415) 423-0913 or (FTS) 543-0913 Neither the United States Government nor the University of California nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial products, process, or service by trade name, trademark manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government nor the University of California, and shall not be used for advertising or product endorsement purposes. Appendix: SUN MICROSYSTEMS SECURITY BULLETIN: This information is only to be used for the purpose of alerting customers to problems. Any other use or re-broadcast of this information without the express written consent of Sun Microsystems shall be prohibited. Sun expressly disclaims all liability for any misuse of this information by any third party. ------------------------------------------------------------------------- These patches are available through your local Sun answer centers worldwide. As well as through anonymous ftp to ftp.uu.net in the ~ftp/sun-dist directory. Please refer to the BugID and PatchID when requesting patches from Sun answer centers. NO README information will be posted in the patch on UUNET. Please refer the the information below for patch installation instructions. ------------------------------------------------------------------------- Sun Bug ID : 1008324 Synopsis : TIOCCONS redirection of console input/output is a security violation. Sun Patch ID : for SunOS 4.1, SunOS 4.1_PSR_A 100187-01 Sun Patch ID : for SunOS 4.1.1 100188-01 Available for: Sun3, Sun3x, Sun4 Sun4c SunOS 4.1, SunOS 4.1_PSR_A, SunOS 4.1.1 Checksum of compressed tarfile on ftp.uu.net:~ftp/sun-dist sum of SunOS 4.1 tarfile 100187-01.tar.Z : 14138 142 sum of SunOS 4.1.1 tarfile 100188-01.tar.Z: 24122 111 -------------------------------------------------------------------------- README information follows: Patch-ID# 100188-01 Keywords: TIOCCONS Synopsis: SunOS 4.1.1: TIOCCONS redirection of console is a security violation. Date: 17/Dec/90 SunOS release: 4.1.1 Unbundled Product: Unbundled Release: Topic: BugId's fixed with this patch: 1008324 Architectures for which this patch is available: sun3 sun3x sun4 sun4c Patches which may conflict with this patch: Obsoleted by: Next major release of SunOS Problem Description: TIOCCONS can be used to re-direct console output/input away from "console" Patch contains kernel object modules for: /sys/sun?/OBJ/cons.o /sys/sun?/OBJ/zs_async.o /sys/sun?/OBJ/mcp_async.o /sys/sun?/OBJ/mti.o Where sun? is one of sun4, sun4c, sun3, sun3x, sun4/490-4.1_PSR_A NOTE: The sun4c does not use mti.o nor mcp_async.o since this architecture does not have VME slots and therefore cannot use the ALM-2 Asynchronous Line Multiplexor or Systech MTI-800/1600. So those modules are not needed. The fix consists of adding permission checking to setcons, the routine that does the work of console redirection, and changing its callers to supply additional information required for the check and to see whether or not the check succeeded. Setcons now uses uid and gid information supplied to it as new arguments to perform a VOP_ACCESS call for VREAD permission on the console. If the caller doesn't have permission to read from the console, setcons rejects the redirection attempt. INSTALL: AS ROOT: save aside the object modules from the FCS tapes as a precaution: # mv /sys/sun?/OBJ/cons.o /sys/sun?/OBJ/cons.o.orig # mv /sys/sun?/OBJ/tty_pty.o /sys/sun?/OBJ/tty_pty.o.orig # mv /sys/sun?/OBJ/zs_async.o /sys/sun?/OBJ/zs_async.o.orig # mv /sys/sun?/OBJ/mcp_async.o /sys/sun?/OBJ/mcp_async.o.orig # mv /sys/sun?/OBJ/mti.o /sys/sun?/OBJ/mti.o.orig copy the new ".o" files to the OBJ directory: # cp sun?/*.o /sys/sun?/OBJ/ build and install a new kernel: rerun /etc/config and do a "make" for the new kernel Please refer to the System and Network Administration Manual for details on how to configure and install a custom kernel. ------------------------------------------------------------------------- Patch-ID# 100187-01 Keywords: TIOCCONS Synopsis: SunOS 4.1 4.1_PSR_A: TIOCCONS redirection of console is a security violation. Date: 17/Dec/90 SunOS release: 4.1 4.1_PSR_A Unbundled Product: Unbundled Release: Topic: BugId's fixed with this patch: 1008324 Architectures for which this patch is available: sun3 sun3x sun4 sun4c sun4-490_4.1_PSR_A Patches which may conflict with this patch: Obsoleted by: Next major release of SunOS Problem Description: TIOCCONS can be used to re-direct console output/ input away from "console" Patch contains kernel object modules for: /sys/sun?/OBJ/cons.o /sys/sun?/OBJ/zs_async.o /sys/sun?/OBJ/mcp_async.o /sys/sun?/OBJ/mti.o Where sun? is one of sun4, sun4c, sun3, sun3x, sun4/490-4.1_PSR_A NOTE: The sun4c does not use mti.o nor mcp_async.o since this architecture does not have VME slots and therefore cannot use the ALM-2 Asynchronous Line Multiplexed or Systech MTI-800/1600. So those modules are not needed. The fix consists of adding permission checking to setcons, the routine that does the work of console redirection, and changing its callers to supply additional information required for the check and to see whether or not the check succeeded. Setcons now uses uid and gid information supplied to it as new arguments to perform a VOP_ACCESS call for VREAD permission on the console. If the caller doesn't have permission to read from the console, setcons rejects the redirection attempt. INSTALL: AS ROOT: save aside the object modules from the FCS tapes as a precaution: # mv /sys/sun?/OBJ/cons.o /sys/sun?/OBJ/cons.o.orig # mv /sys/sun?/OBJ/tty_pty.o /sys/sun?/OBJ/tty_pty.o.orig # mv /sys/sun?/OBJ/zs_async.o /sys/sun?/OBJ/zs_async.o.orig # mv /sys/sun?/OBJ/mcp_async.o /sys/sun?/OBJ/mcp_async.o.orig # mv /sys/sun?/OBJ/mti.o /sys/sun?/OBJ/mti.o.orig copy the new ".o" files to the OBJ directory: # cp sun?/*.o /sys/sun?/OBJ/ build and install a new kernel: rerun /etc/config and do a "make" for the new kernel Please refer to the System and Network Administration Manual for details on how to configure and install a custom kernel.