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. Get paid for vulnerability research http://labs.idefense.com/methodology/vulnerability/vcp.php Free tools, research and upcoming events http://labs.idefense.com/ X. LEGAL NOTICES Copyright © 2007 iDefense, Inc. Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please e-mail customerservice@idefense.com for permission. Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.