CVE-2022-20941 The web-based management interface of Cisco Firepower could be vulnerable to an unauthenticated, remote attacker who could access sensitive information.
To exploit this vulnerability, an attacker would need to send a series of HTTPS requests to an affected device. There are several possible ways to do this. For example, the attacker could use a web-based redirection attack or launch a man-in-the-middle attack on the management traffic between the device and the management server. An attacker could also exploit this vulnerability by sending a series of HTTPS requests to the management server and receiving a response containing resource names that do not have sufficient entropy. By observing the results of these requests, the attacker could then construct an attack against the device. Depending on the type of device, the attacker could then execute any of the attacks outlined in the previous section. Cisco has confirmed this vulnerability and released software updates. However, there are also several things that users can do to protect themselves. Users can restrict access to the management interface to only trusted users. If possible, management traffic should use a secure channel such as a virtual private network (VPN) connection or encrypted link. In addition, users can ensure that their management server has sufficient entropy to protect themselves against this type of attack.
Cisco device types that are susceptible to spoofing attacks
Cisco Systems has confirmed a vulnerability in their Cisco Prime OS software. The vulnerability allows an attacker to send a series of HTTPS requests to an affected device and receive responses containing resource names that do not have sufficient entropy. By observing the results of these requests, the attacker could then construct an attack against the device. Depending on the type of device, the attacker could then execute any of the attacks outlined in the previous section.
Vulnerability Detection Methods
The vulnerability detection methods outlined in this section can help to detect an attack and mitigate the risk of exploitation. The following are four possible ways that a device may be vulnerable to this type of attack.
1) Observing the results of HTTP requests made by the management server: When a user performs an HTTPS request on their management interface, the device will send all of its available resources for evaluation. This particular observation can be used as a potential indicator that an adversary is performing an attack against the device. For example, if users see unexpected changes in resource name or other content, they should consider whether or not they have been subject to one of the attacks outlined in this document.
2) Restricting access to management traffic: This particular method can block out potential adversaries attempting to exploit this vulnerability. If possible, management traffic should use a secure channel such as a virtual private network (VPN) connection or encrypted link. In addition, it’s recommended that devices use HTTPS while performing management traffic so that they can ensure security throughout their entire communication process.
3) Using entropy on the management server: It is important for management servers to have sufficient entropy to prevent attackers from exploiting vulnerabilities such as these with brute force attacks. If possible, entropy should be set at 4 bits per byte so that it would require 4 billion requests before enough information could be gathered to exploit this vulnerability successfully.
4) Implementing logging mechanisms: Consider implementing logging mechanisms into your system so that you can monitor your
Stack-Based Buffer Overflow Exploit
This vulnerability affects Cisco’s switch, router and firewall products. If successful, an attacker would be able to cause a stack-based buffer overflow on the device by sending malformed network traffic that triggers a memory corruption error. This vulnerability is exploitable remotely without authentication because it uses the same HTTP connection that is used for management traffic. This vulnerability is not considered high risk because it requires user interaction to exploit.
Vulnerability Discovery
On October 9, 2017, Cisco released an advisory that detailed a vulnerability in the management interface of devices running the Cisco IOS and Cisco IOS XE software. This vulnerability can be exploited by sending a series of malicious HTTPS requests to an affected device. The write-up goes on to state that the attacker could then execute any of the attacks outlined in Section 4 of this write-up.
Timeline
Published on: 11/15/2022 21:15:00 UTC
Last modified on: 11/21/2022 15:23:00 UTC