A vulnerability in the implementation of a specific CLI command and the associated Simple Network Management Protocol (SNMP) MIB for Cisco NX-OS (in standalone NX-OS mode) on Cisco Nexus 3000 and 9000 Series Switches could allow an authenticated, remote attacker to exhaust system memory on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to the incorrect implementation of the CLI command, resulting in a failure to free all allocated memory upon completion. An attacker could exploit this vulnerability by authenticating to the affected device and repeatedly issuing a specific CLI command or sending a specific SNMP poll request for a specific Object Identifier (OID). A successful exploit could allow the attacker to cause the IP routing process to restart or to cause a device reset, resulting in a DoS condition. Cisco Bug IDs: CSCvf23136.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Nx-os | Cisco | 7.0(3)i5(2) (including) | 7.0(3)i5(2) (including) |
| Nx-os | Cisco | 7.0(3)i6(1) (including) | 7.0(3)i6(1) (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.