CERT® Advisory CA-1993-12 Novell LOGIN.EXE VulnerabilityOriginal issue date: September 16, 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 concerning a security vulnerability in Novell's NetWare 4.x login program (LOGIN.EXE). This vulnerability affects NetWare 4.0 and 4.01. It does not affect NetWare 2.x, NetWare 3.x, or Netware for UNIX.
Novell is making available a security enhancement to the login program for NetWare 4.x. CERT strongly recommends that sites using of Novell NetWare 4.X replace their current LOGIN.EXE program on all affected systems with this security-enhanced version as soon as possible.
A security vulnerability exists in LOGIN.EXE in Novell NetWare 4.X. In some environments, a user's name and password may be temporarily written to disk.
User accounts may be readily compromised.
NetWare 4.x sites should obtain and install on all affected systems the security-enhanced LOGIN.EXE program. CERT strongly recommends that sites replace their current LOGIN.EXE with the security-enhanced version as soon as possible.
This new file is available via anonymous FTP from first.org. The files are located in:
Filename Size Checksum -------- ------ ----------------------------- /pub/software/seclog.exe 166276 00193 163 (Standard UNIX Sum) 58886 325 (System V Sum)
This file is also available at no charge through NetWare resellers, on NetWire in library 14 of the NOVLIB forum, or by calling +1-800-NETWARE. NetWare customers outside the U.S. may call Novell at +1-303-339-7027 or +31-55-384279 or may fax a request for SECLOG.EXE v4.02 to Novell at +1-303-330-7655 or +31-55-434455. Fax requests should include company name, contact name, postal address, and phone number.
The distribution SECLOG.EXE is a self-extracting archive that contains a patched file and a text file of installation instructions. The patch file (LOGIN.EXE) and the text file (SECLOG.TXT) are created by executing the distribution file SECLOG.EXE. After extracting the files, the dir command should produce the following output:
SECLOG EXE 166276 xx-xx-xx xx:xxx LOGIN EXE 354859 08-25-93 11:43a SECLOG TXT 5299 09-02-93 11:16a
Note that the date and time shown for SECLOG.EXE will reflect when this file was created on your system.
To install the patch, follow the directions contained in the text file SECLOG.TXT.
After installing the patch, sites should instruct all users to change their passwords.
The CERT Coordination Center would like to thank Karyn Pichnarczyk and the contribution of CIAC to this advisory. We would also like to acknowledge Richard Colby of Chem Nuclear Geotech, Inc., for reporting this vulnerability to CIAC, and Novell for their efforts in the resolution of this vulnerability.
This document is available from: http://www.cert.org/advisories/CA-1993-12.html
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Copyright 1993 Carnegie Mellon University.
September 19,1997 Attached Copyright Statement