Cisco Wireless LAN Controller Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition on a targeted system. Updates are not available.
A vulnerability in Cisco Wireless LAN Controller Software could allow
an unauthenticated, remote attacker to create a denial of service (DoS)
condition for remote login Telnet sessions.
The vulnerability is due to improper cleanup of incorrectly terminated remote login sessions. An exploit could allow an attacker to exhaust available Telnet sessions and deny service to new administrator Telnet sessions.
Cisco has confirmed the vulnerability in a security notice; however, software updates are not available.
At the time this alert was first published, Cisco Wireless LAN Controller Software versions 7.4(1.54) and prior were vulnerable. Later versions of Cisco Wireless LAN Controller Software may also be affected.
Customers are advised to review the bug reports in the "Vendor Announcements" section for a current list of affected versions.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
An unauthenticated, remote attacker could exploit this vulnerability to exhaust available Telnet sessions, denying service to new Administrator Telnet sessions, which could result in a DoS condition.
The vulnerability is due to improper cleanup of incorrectly terminated remote login sessions by the affected software.
An unauthenticated, remote attacker could exploit this vulnerability to exhaust available Telnet sessions and deny service to new administrator Telnet sessions. Successful exploitation could result in a DoS condition.
Administrators are advised to contact the vendor regarding future updates and releases.
Administrators are advised to allow only trusted users to have network access.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators are advised to monitor affected systems.
The urgency and severity ratings of this alert are not tailored to individual users; users may value alerts differently based upon their network configurations and circumstances. THE ALERT, AND INFORMATION CONTAINED THEREIN, ARE PROVIDED ON AN "AS IS" BASIS AND DO NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE ALERT, AND INFORMATION CONTAINED THEREIN, OR MATERIALS LINKED FROM THE ALERT, IS AT YOUR OWN RISK. INFORMATION IN THIS ALERT AND ANY RELATED COMMUNICATIONS IS BASED ON OUR KNOWLEDGE AT THE TIME OF PUBLICATION AND IS SUBJECT TO CHANGE WITHOUT NOTICE. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE ALERTS AT ANY TIME.