Attack vector
NETWORK Attack complexity
MEDIUM Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
COMPLETE Published: 2018-10-05
Updated: 2020-08-31
Summary
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.
Vulnerable Configurations
| Part | Description | Count |
| Application | Cisco | 4 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Leveraging Race Conditions
This attack targets a race condition occurring when multiple processes access and manipulate the same resource concurrently and the outcome of the execution depends on the particular order in which the access takes place. The attacker can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance a race condition can occur while accessing a file, the attacker can trick the system by replacing the original file with his version and cause the system to read the malicious file.
- Leveraging Race Conditions via Symbolic Links
This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to her. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file she will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
Nessus
| NASL family | CISCO |
| NASL id | CISCO-SA-20181003-FTD-INSPECT-DOS.NASL |
| description | According to its self-reported version, the Cisco Firepower Threat Defense Software is affected by multiple DoS vulnerabilities. Please see the included Cisco BIDs and the Cisco Security Advisory for more information. |
| last seen | 2020-04-30 |
| modified | 2018-10-04 |
| plugin id | 117917 |
| published | 2018-10-04 |
| reporter | This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. |
| source | https://www.tenable.com/plugins/nessus/117917 |
| title | Cisco Firepower Threat Defense Software Multiple DoS Vulnerabilities (cisco-sa-20181003-ftd-inspect-dos, cisco-sa-20181003-asa-dma-dos) |