CVE-2018-15390: Cisco Firepower Threat Defense Software FTP Inspection Denial of Service Vulnerability
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Configuration
If configured to apply FTP inspection to transit traffic, change the configuration so that the access control rule for transit traffic is not associated with an FTP file policy (or otherwise disable FTP inspection), to avoid triggering the DoS condition caused by the FTP inspection engine failing to release spinlocks under low-memory conditions.
Cisco Firepower Threat Defense (FTD) Software - FTP inspection engine FTP inspection and FTP file policy usage for transit traffic = Disable FTP inspection and/or ensure the access control rule for transit traffic is not associated with an FTP file policy
Event History
Frequently Asked Questions
What is the severity of CVE-2018-15390?
CVE-2018-15390 is rated as high severity due to its potential to allow an unauthenticated remote attacker to cause a denial of service.
How do I fix CVE-2018-15390?
To mitigate CVE-2018-15390, upgrade your Cisco Firepower Threat Defense Software to a version superior to 6.2.3.4.
Which versions of Cisco Firepower Threat Defense are affected by CVE-2018-15390?
CVE-2018-15390 affects Cisco Firepower Threat Defense versions from 6.2.3.0 to 6.2.3.4.
What impact does CVE-2018-15390 have on affected systems?
The impact of CVE-2018-15390 is that it can cause a denial of service condition on affected Cisco devices.
Is there a workaround for CVE-2018-15390?
There are no known workarounds for CVE-2018-15390 other than applying the appropriate software update.