A vulnerability in the locally significant certificate (LSC) provisioning feature of Cisco Catalyst 9800 Series Wireless Controllers that are running Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a memory leak that could lead to a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain public key infrastructure (PKI) packets. An attacker could exploit this vulnerability by sending crafted Secure Sockets Layer (SSL) packets to an affected device. A successful exploit could cause an affected device to continuously consume memory, which could result in a memory allocation failure that leads to a crash and causes a DoS condition.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Ios_xe | Cisco | 16.1.1 (including) | 16.1.1 (including) |
| Ios_xe | Cisco | 16.1.2 (including) | 16.1.2 (including) |
| Ios_xe | Cisco | 16.1.3 (including) | 16.1.3 (including) |
| Ios_xe | Cisco | 16.2.1 (including) | 16.2.1 (including) |
| Ios_xe | Cisco | 16.2.2 (including) | 16.2.2 (including) |
| Ios_xe | Cisco | 16.3.1 (including) | 16.3.1 (including) |
| Ios_xe | Cisco | 16.3.1a (including) | 16.3.1a (including) |
| Ios_xe | Cisco | 16.3.2 (including) | 16.3.2 (including) |
| Ios_xe | Cisco | 16.3.3 (including) | 16.3.3 (including) |
| Ios_xe | Cisco | 16.3.4 (including) | 16.3.4 (including) |
| Ios_xe | Cisco | 16.3.5 (including) | 16.3.5 (including) |
| Ios_xe | Cisco | 16.3.5b (including) | 16.3.5b (including) |
| Ios_xe | Cisco | 16.3.6 (including) | 16.3.6 (including) |
| Ios_xe | Cisco | 16.3.7 (including) | 16.3.7 (including) |
| Ios_xe | Cisco | 16.3.8 (including) | 16.3.8 (including) |
| Ios_xe | Cisco | 16.3.9 (including) | 16.3.9 (including) |
| Ios_xe | Cisco | 16.4.1 (including) | 16.4.1 (including) |
| Ios_xe | Cisco | 16.4.2 (including) | 16.4.2 (including) |
| Ios_xe | Cisco | 16.4.3 (including) | 16.4.3 (including) |
| Ios_xe | Cisco | 16.5.1 (including) | 16.5.1 (including) |
| Ios_xe | Cisco | 16.5.1a (including) | 16.5.1a (including) |
| Ios_xe | Cisco | 16.5.1b (including) | 16.5.1b (including) |
| Ios_xe | Cisco | 16.5.2 (including) | 16.5.2 (including) |
| Ios_xe | Cisco | 16.5.3 (including) | 16.5.3 (including) |
| Ios_xe | Cisco | 16.7.1 (including) | 16.7.1 (including) |
| Ios_xe | Cisco | 16.7.2 (including) | 16.7.2 (including) |
| Ios_xe | Cisco | 16.7.3 (including) | 16.7.3 (including) |
| Ios_xe | Cisco | 16.8.1 (including) | 16.8.1 (including) |
| Ios_xe | Cisco | 16.8.1a (including) | 16.8.1a (including) |
| Ios_xe | Cisco | 16.8.1b (including) | 16.8.1b (including) |
| Ios_xe | Cisco | 16.8.1c (including) | 16.8.1c (including) |
| Ios_xe | Cisco | 16.8.1s (including) | 16.8.1s (including) |
| Ios_xe | Cisco | 16.8.2 (including) | 16.8.2 (including) |
| Ios_xe | Cisco | 16.8.3 (including) | 16.8.3 (including) |
| Ios_xe | Cisco | 16.10.1 (including) | 16.10.1 (including) |
| Ios_xe | Cisco | 16.10.1a (including) | 16.10.1a (including) |
| Ios_xe | Cisco | 16.10.1b (including) | 16.10.1b (including) |
| Ios_xe | Cisco | 16.10.1e (including) | 16.10.1e (including) |
| Ios_xe | Cisco | 16.10.1s (including) | 16.10.1s (including) |
| Ios_xe | Cisco | 16.10.2 (including) | 16.10.2 (including) |
| Ios_xe | Cisco | 16.10.3 (including) | 16.10.3 (including) |
| Ios_xe | Cisco | 16.11.1 (including) | 16.11.1 (including) |
| Ios_xe | Cisco | 16.11.1a (including) | 16.11.1a (including) |
| Ios_xe | Cisco | 16.11.1b (including) | 16.11.1b (including) |
| Ios_xe | Cisco | 16.11.1c (including) | 16.11.1c (including) |
| Ios_xe | Cisco | 16.11.1s (including) | 16.11.1s (including) |
| Ios_xe | Cisco | 16.12.1 (including) | 16.12.1 (including) |
| Ios_xe | Cisco | 16.12.1a (including) | 16.12.1a (including) |
| Ios_xe | Cisco | 16.12.1c (including) | 16.12.1c (including) |
| Ios_xe | Cisco | 16.12.1s (including) | 16.12.1s (including) |
| Ios_xe | Cisco | 16.12.2 (including) | 16.12.2 (including) |
| Ios_xe | Cisco | 16.12.2a (including) | 16.12.2a (including) |
| Ios_xe | Cisco | 16.12.4 (including) | 16.12.4 (including) |
| Ios_xe | Cisco | 16.12.8 (including) | 16.12.8 (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.