CERT^® Advisory CA-1991-23 Hewlett Packard/Apollo Domain/OS crp Vulnerability

A complete revision history is at the end of this file.

The Computer Emergency Response Team/Coordination Center (CERT/CC) has received information concerning a vulnerability in the crp facility in Hewlett Packard/Apollo Domain/OS. This vulnerability is present on all HP/Apollo Domain/OS SR10 systems up through SR10.3. Patches that address this problem will be available in the SR10.3 patch tape (~Feb 92) and in the SR10.4 software release. Contact your local sales office for more information.

I. Description

II. Impact

III. Workaround

Create a file "crplib.c" containing the four-line C program:

	extern void pad_$dm_cmd(void);
	void pad_$dm_cmd() { }
	extern void pad_$def_pfk(void);
        void pad_$def_pfk() { }

Compile this program using '-pic':

	(AEGIS)  /com/cc crplib.c -pic
        (UNIX)   /bin/cc -c crplib.c -W0,-pic
	

Copy the result to somewhere accessible to all users (/lib/crplib is recommended).

	(AEGIS)  /com/cpf crplib.bin /lib/crplib
        (AEGIS)  /com/edacl -p root prwx -g wheel rx -w rx /lib/crplib

	(UNIX)   /bin/cp crplib.o /lib/crplib

        (UNIX)   /bin/chmod 755 /lib/crplib
	

a) Ensure that all users do an 'inlib' of that file before running crp.

One way to ensure this would be to replace the /usr/apollo/bin/crp command by a shell script that does the inlib. Doing this step will force crp to use the null functions defined in step 1 above.

	(AEGIS)  /com/chn /usr/apollo/bin/crp crp.orig
        (UNIX)   /bin/mv /usr/apollo/bin/crp /usr/apollo/bin/crp.orig
	

b) Create the file /usr/apollo/bin/crp containing the shell script:

	(AEGIS)	#!/com/sh
          /com/sh -c inlib /lib/crplib ';' /usr/apollo/bin/crp.orig ^*
	(UNIX)	#!/bin/sh
		inlib /lib/crplib
                exec /usr/apollo/bin/crp.orig "$@"
	

c) Make this script executable.

        (AEGIS)	/com/edacl -p root prwx -g wheel rx -w rx /usr/apollo/bin/crp
        (UNIX)	/bin/chmod 755 /usr/apollo/bin/crp

NOTE: This workaround will prevent crp from making use of the two system calls; and therefore, it may affect the functionality of various software programs since they will be unable to define programmable function keys, create new windows on the client node, or execute background processes using the Display Manager interface.

The CERT/CC wishes to thank Paul Szabo of the University of Sydney for bringing this problem to our attention and providing a workaround. We would also like to thank Jim Richardson of the University of Sydney for his assistance and Hewlett Packard/Apollo for their timely response to the report of this vulnerability.

CERT/CC Contact Information

Email: cert@cert.org
Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:

CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh PA 15213-3890
U.S.A.

CERT/CC personnel answer the hotline 08:00-17:00 EST(GMT-5) / EDT(GMT-4) Monday through Friday; they are on call for emergencies during other hours, on U.S. holidays, and on weekends.

Using encryption

We strongly urge you to encrypt sensitive information sent by email. Our public PGP key is available from

http://www.cert.org/CERT_PGP.key

If you prefer to use DES, please call the CERT hotline for more information.

Getting security information

CERT publications and other security information are available from our web site

http://www.cert.org/

* "CERT" and "CERT Coordination Center" are registered in the U.S. Patent and Trademark Office.

NO WARRANTY
Any material furnished by Carnegie Mellon University and the Software Engineering Institute is furnished on an "as is" basis. Carnegie Mellon University makes no warranties of any kind, either expressed or implied as to any matter including, but not limited to, warranty of fitness for a particular purpose or merchantability, exclusivity or results obtained from use of the material. Carnegie Mellon University does not make any warranty of any kind with respect to freedom from patent, trademark, or copyright infringement.

Copyright 1991 Carnegie Mellon University.

September 18,1997  Attached Copyright Statement