Date: Thu, 27 Dec 2001 11:18:53 -0500 (EST)
From: EnGarde Secure Linux <[email protected]>
To: [email protected], [email protected]Subject: [ESA-20011227-01] stunnel format string vulnerability
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| EnGarde Secure Linux Security Advisory December 27, 2001 |
| http://www.engardelinux.org/ ESA-20011227-01 |
| |
| Package: stunnel |
| Summary: There is a format string vulnerability in stunnel. |
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EnGarde Secure Linux is a secure distribution of Linux that features
improved access control, host and network intrusion detection, Web
based secure remote management, complete e-commerce using AllCommerce,
and integrated open source security tools.
OVERVIEW
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There is a format string vulnerability in stunnel which may allow an
attacker to exploit a victim by impersonating a mail server.
DETAIL
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There are a couple of instances in stunnel where a format is not passed
to a printf-like function, leading to your classic format string
vulnerability. It is not know weather or not it is exploitable at this
time but all users are recommended to upgrade in any event.
This vulnerability was disclosed on December 18 by Matthias Lange on
the stunnel-users mailing list. The original message may be found here:
http://marc.theaimsgroup.com/?l=stunnel-users&m=100868569203440&w=3
All users should upgrade to the most recent version, as outlined in
SOLUTION
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All users should upgrade to the most recent version as outlined in
this advisory. All updates may be found at:
ftp://ftp.engardelinux.org/pub/engarde/stable/updates/http://ftp.engardelinux.org/pub/engarde/stable/updates/
Before upgrading the package, the machine must either:
a) be booted into a "standard" kernel; or
b) have LIDS disabled.
To disable LIDS, execute the command:
# /sbin/lidsadm -S -- -LIDS_GLOBAL
To install the updated package, execute the command:
# rpm -Uvh <filename>
You must now update the LIDS configuration by executing the command:
# /usr/sbin/config_lids.pl
To re-enable LIDS (if it was disabled), execute the command:
# /sbin/lidsadm -S -- +LIDS_GLOBAL
To verify the signatures of the updated packages, execute the command:
# rpm -Kv <filename>
UPDATED PACKAGES
- ----------------
These updated packages are for EnGarde Secure Linux 1.0.1 (Finestra).
Source Packages:
SRPMS/stunnel-3.22-1.0.4.src.rpm
MD5 Sum: e408662d6fc54f3979642c9e8c110ba4
Binary Packages:
i386/stunnel-3.22-1.0.4.i386.rpm
MD5 Sum: 482ff9210541d73b114404ccb9732cf0
i686/stunnel-3.22-1.0.4.i686.rpm
MD5 Sum: afad91053b8d482e36e85251fab06755
REFERENCES
- ----------
Guardian Digital's public key:
http://ftp.engardelinux.org/pub/engarde/ENGARDE-GPG-KEY
Credit for the discovery of this bug goes to:
Matthias Lange <[email protected]>
stunnel's Official Web Site:
http://stunnel.mirt.net/
Security Contact: [email protected]
EnGarde Advisories: http://www.engardelinux.org/advisories.html
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$Id: ESA-2001122701-stunnel,v 1.2 2001/12/27 16:02:00 rwm Exp $
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Author: Ryan W. Maple, <[email protected]>
Copyright 2001, Guardian Digital, Inc.
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