CERT® Advisory CA-1993-13 SCO Home Directory VulnerabilityOriginal issue date: September 17, 1993
Last revised: September 19, 1997
Attached copyright statement
A complete revision history is at the end of this file.
The CERT Coordination Center has received information indicating that SCO Operating Systems may be vulnerable to a potential compromise of system security. This vulnerability allows unauthorized access to the "dos" and "asg" accounts, and, as a result of this access, unauthorized access to the "root" account may also occur.
The following releases of SCO products are affected by this vulnerability:
SCO UNIX System V/386 Release 3.2 Operating System SCO UNIX System V/386 Release 3.2 Operating System Version 2.0 SCO UNIX System V/386 Release 3.2 Operating System version 4.x SCO UNIX System V/386 Release 3.2 Operating System Version 4.0 with Maintenance Supplement Version 4.1 and/or Version 4.2 SCO Network Bundle Release 4.x SCO Open Desktop Release 1.x SCO Open Desktop Release 2.0 SCO Open Desktop Lite Release 3.0 SCO Open Desktop Release 3.0 SCO Open Server Network System Release 3.0 SCO Open Server Enterprise System Release 3.0
CERT and The Santa Cruz Operation recommend that all sites using these SCO products take action to eliminate the source of vulnerability from their systems. This problem will be corrected in upcoming releases of SCO operating systems.
The home directories of the users "dos" and "asg" are /tmp and /usr/tmp respectively. These directories are designed to have global write permission.
This vulnerability may allow unauthorized users to gain access to these accounts. This vulnerability may also corrupt certain binaries in the system and thus prevent regular users from running them, as well as introduce a potential for unauthorized root access.
All affected sites should follow these instructions:
Electronic mail: support@sco.COM
USA/Canada: 6am-5pm Pacific Daylight Time (PDT)
Pacific Rim, Asia, and Latin American customers: 6am-5pm Pacific (PDT)
Europe, Middle East, Africa: 9am-5:30pm British Standard Time (BST)
+44 (0)923 816344 (voice)
The CERT Coordination Center wishes to thank Christopher Durham of the Santa Cruz Operation for reporting this problem and his assistance in responding to this problem.
This document is available from: http://www.cert.org/advisories/CA-1993-13.html
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Copyright 1993 Carnegie Mellon University.
September 19,1997 Attached Copyright Statement