VIGILANTe Security Watch Advisory
 
Name: Cisco Aironet AP 1100 Malformed HTTP Request Crash Vulnerability
Systems Affected: Tested on a Cisco Aironet AP1100 Model 1120B Series
Wireless device.
Firmware version 12.2(4)JA and earlier.
Severity: High Risk
Vendor URL: http://www.vigilante.com
Authors: Reda Zitouni (reda.zitouni@vigilante.com)
Date: 28th July 2003
Advisory Code: VIGILANTE-2003001
 
Description
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Cisco Aironet 1100 Series Access Point is a device manufactured by Cisco
Systems offering a WLAN solution based on the 802.11b Wifi standard.
The Arionet Bridge is vulnerable to a denial of service.This can be
exploited remotely by an attacker. No user login or password is
necessary.
 
Details
*******
 
It is possible to cause Cisco Aironet Access Point to crash and reboot
if the HTTP server feature is enabled. This can be accomplished by
submitting a specially crafted request to the web server. There is no
need to authenticate to perform this attack, only access to the web
server is required. The Aironet bridge reboots upon receiving the
request and failing to handle correctly this one. Afterwards, no further
access to the WLAN or its services is possible.
 
Vendor status:
**************
Cisco was contacted June 19, 2003 and answered the same day. 5 days
later, they told us that they would release a patch soon. The patch was
finally released July 3, 2003.
 
Vulnerability Assessment:
A test case to detect this vulnerability was added to SecureScan NX in
the upgrade package of July 28, 2003. You can see the documentation of
this test case 17655 on SecureScan NX web site at
http://securescannx.vigilante.com/tc/17655 . 
Fix:  A firmware upgrading the Aironet IOS version to c1100-k9w7 has
been released by Cisco. Please note that this version fixes some other
bugs as TC 15438 (refer to release note).
 
Workaround:
***********
1. If not needed - disable access to the web feature on the Aironet
Bridge. 
2. If needed - restrict access to the HTTP service for outside
connections.
CVE: Common Vulnerabilities and Exposures group ( reachable at
http://cve.mitre.org/ ) was contacted and assigned CAN-2003-0511 to this
vulnerability. 
 
Links:
*****
Cisco Advisory:
http://www.cisco.com/warp/public/707/cisco-sa-20030728-ap1x00.shtml
Vigilante Advisory:
http://www.vigilante.com/inetsecurity/advisories/VIGILANTE-2003001.htm
Product Homepage:  http://www.cisco.com/warp/public/cc/pd/witc/ps4570
CVE: CAN-2003-0511
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-CAN-2003-0511
 

Credit:
******
This vulnerability was discovered by Reda Zitouni, member of our
Security Watch Team at VIGILANTe. 
We wish to thank Cisco PSIRT Team for their fast answer to fix this
problem. 
 
Copyright VIGILANTe.com, Inc. 2003-07-28
 
Disclaimer:
**********
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Feedback:
********
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