Juniper Advisory
PR09-05: ScreenOS remote information disclosure on Juniper Netscreen ScreenOS
Firewalls
Vulnerability found: 22nd March 2009
Vendor informed: 22nd March 2009
Severity: Low (information disclosure)
Description:
By simply requesting the about.html file, the firewall returns the version of
ScreenOS and patch level used and the feature set.
No authentication is needed to retrieve this information on the firewall's OS.
It is common to find exposed ScreenOS WebUI firewall management front-ends on
the Internet, attackers might use the exposed information to carry out targeted
attacks knowing the version and patch level of the firmware used.
Successfully tested on:
Juniper Networks SSG 320 ScreenOS Version: 6.2.0r1.0
Juniper Networks netscreen SSG 520 ScreenOS Version:6.1.0r1.0
Juniper Networks netscreen 208 ScreenOS Version: 5.4.0r10.0
Proof of concept:
http://target-domain.foo/about.html
https://target-domain.foo/about.html
Returns:
Juniper Networks, Inc.
Version: 6.2.0r1.0 (Firewall+VPN)
ScreenOS WebUI
Copyright © 1997-2008 Juniper Networks, Inc.
All Rights Reserved.
For the latest technical information visit:
http://www.juniper.net
Consequences:
A remote attacker could recover information with regards to the target site's
operating system version and patch level.
This kind of information might be useful to attackers in certain scenarios.
i.e.: when attempting to exploit published
vulnerabilities in a outdated version of ScreenOS.
Fix:
Ensure that the firewall's management interface is disabled on the Internet
connected interface, by disabling WeBUI within service
options on the Internet connected interface.
Juniper Networks have released the 6.2.0r2.0, 6.2R2 and 5.4.0r12 software
updates on the 8th April 2009 which solves the issue.
Vendor feedback:-
Juniper stated that no security advisory is needed to be released due to the
low CVSS score of the vulnerability, and Juniper knew of the issue already.
Procheckup found this issue affected different Juniper firewall firmware, going
back to at least 2006.
References:
http://www.procheckup.com/Vulnerabilities.php
http://www.juniper.net/us/en/products-services/security/ssg-series/
Credits: Richard Brain of ProCheckUp Ltd (www.procheckup.com)
Legal:
Copyright 2009 Procheckup Ltd. All rights reserved.
Permission is granted for copying and circulating this Bulletin to the Internet
community for the purpose of alerting them to
problems, if and only if, the Bulletin is not edited or changed in any way, is
attributed to Procheckup, and provided such
reproduction and/or distribution is performed for non-commercial purposes.
Any other use of this information is prohibited. Procheckup is not liable for
any misuse of this information by any third party.