Novell is now a part of Micro Focus

Security bugfix for package at


(Last modified: 15JAN2002)

solutions Security bugfix for package at SuSE Linux Maintenance Web (98802ea84cfe0c8baae21504bf3af5a6)

Applies to

Product(s): SuSE Linux Database Server
SuSE Linux Admin-CD for Firewall
SuSE eMail Server III
SuSE Linux Enterprise Server 7 for IA32
SuSE Linux Enterprise Server 7 for IA64
SuSE Linux Enterprise Server 7 for S/390 and zSeries
SuSE Linux Enterprise Server for S/390
SuSE Firewall Adminhost VPN
SuSE Linux Connectivity Server

Package: a1/at
Architecture: i386,ia64,s390
Release: 20020115
Obsoletes: none


This update should always be installed.



Problem description

The at command reads commands from standard input for execution at a later time that is specified on the command line. If such an execution time is given in a carefully drafted wrong format, the at command may crash as a result of a surplus call to free(). The cause of the crash is a heap corruption that is exploitable under certain circumstances since the /usr/bin/at command is installed setuid root.
A temporary workaround against the bug is to disable the at command for non-root users by removing the setuid-bit from the /usr/bin/at command. As a permanent solution it is recommended to install this update package. In addition to the fixed heap corruption, file handling security has been improved by adding the O_EXCL (exclusive) option to an open(2) system call inside the at(1) code.


Please install the updates provided at the location noted below.

Installation notes

This update is provided as an RPM package that can easily be installed onto a running system by using this command:
rpm -Uvh at.rpm

links to download packages

Download Source Packages

Download the source code of the patches for maintained products.


The Origin of this information may be internal or external to Novell. Novell makes all reasonable efforts to verify this information. However, the information provided in this document is for your information only. Novell makes no explicit or implied claims to the validity of this information.

Any trademarks referenced in this document are the property of their respective owners. Consult your product manuals for complete trademark information.

© Micro Focus