A vulnerability in the Cisco Aironet Series Access Points (APs) software could allow an authenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a deadlock condition that may occur when an affected AP attempts to dequeue aggregated traffic that is destined to an attacker-controlled wireless client. An attacker who can successfully transition between multiple Service Set Identifiers (SSIDs) hosted on the same AP while replicating the required traffic patterns could trigger the deadlock condition. A watchdog timer that detects the condition will trigger a reload of the device, resulting in a DoS condition while the device restarts.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Aironet_access_points | Cisco | 8.2(166.0) (including) | 8.2(166.0) (including) |
| Aironet_access_points | Cisco | 8.2(167.3) (including) | 8.2(167.3) (including) |
| Aironet_access_points | Cisco | 8.3(133.0) (including) | 8.3(133.0) (including) |
| Aironet_access_points | Cisco | 8.3(141.10) (including) | 8.3(141.10) (including) |
| Aironet_access_points | Cisco | 8.5(120.0) (including) | 8.5(120.0) (including) |
| Aironet_access_points | Cisco | 8.7(1.96) (including) | 8.7(1.96) (including) |
| Aironet_access_points | Cisco | 8.7(1.99) (including) | 8.7(1.99) (including) |
| Aironet_access_points | Cisco | 8.7(1.107) (including) | 8.7(1.107) (including) |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.