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ESB-2013.0625 - [Debian] stunnel4: Execute arbitrary code/commands - Remote with user interaction
Date: 03 May 2013
Original URL: http://www.auscert.org.au/render.html?cid=1980&it=17483
References: ESB-2013.0491  

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             AUSCERT External Security Bulletin Redistribution

                               ESB-2013.0625
                         stunnel4 security update
                                3 May 2013

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        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           stunnel4
Publisher:         Debian
Operating System:  Debian GNU/Linux 6
Impact/Access:     Execute Arbitrary Code/Commands -- Remote with User Interaction
Resolution:        Patch/Upgrade
CVE Names:         CVE-2013-1762  

Reference:         ESB-2013.0491

Original Bulletin: 
   http://www.debian.org/security/2013/dsa-2664

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Debian Security Advisory DSA-2664-1                   security@debian.org
http://www.debian.org/security/                      Salvatore Bonaccorso
May 2, 2013                            http://www.debian.org/security/faq
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Package        : stunnel4
Vulnerability  : buffer overflow
Problem type   : remote
Debian-specific: no
CVE ID         : CVE-2013-1762
Debian Bug     : 702267

Stunnel, a program designed to work as an universal SSL tunnel for
network daemons, is prone to a buffer overflow vulnerability when using
the Microsoft NT LAN Manager (NTLM) authentication
("protocolAuthentication = NTLM") together with the 'connect' protocol
method ("protocol = connect"). With these prerequisites and using
stunnel4 in SSL client mode ("client = yes") on a 64bit host, an attacker
could possibly execute arbitrary code with the privileges of the stunnel
process, if the attacker can either control the specified proxy server or
perform man-in-the-middle attacks on the tcp session between stunnel and
the proxy sever.

Note that for the testing distribution (wheezy) and the unstable
distribution (sid), stunnel4 is compiled with stack smashing protection
enabled, which should help protect against arbitrary code execution.

For the stable distribution (squeeze), this problem has been fixed in
version 3:4.29-1+squeeze1.

For the testing distribution (wheezy), this problem has been fixed in
version 3:4.53-1.1.

For the unstable distribution (sid), this problem has been fixed in
version 3:4.53-1.1.

We recommend that you upgrade your stunnel4 packages.

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: http://www.debian.org/security/

Mailing list: debian-security-announce@lists.debian.org
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===========================================================================
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