A vulnerability in the FTP inspection engine of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software fails to release spinlocks when a device is running low on system memory, if the software is configured to apply FTP inspection and an access control rule to transit traffic, and the access control rule is associated with an FTP file policy. An attacker could exploit this vulnerability by sending a high rate of transit traffic through an affected device to cause a low-memory condition on the device. A successful exploit could allow the attacker to cause a software panic on the affected device, which could cause the device to reload and result in a temporary DoS condition.
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Firepower_threat_defense | Cisco | 6.2.3.0 (including) | 6.2.3.4 (including) |
Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.