Cisco Adaptive Security Appliance (ASA) XSS (CVE-2020-3580)
Description
A cross-site scripting (XSS) vulnerability exists in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software. This vulnerability allows an unauthenticated, remote attacker to inject malicious scripts into the web interface, which are then executed in the context of authenticated users who interact with specially crafted links or content.
Remediation
Apply the security updates provided by Cisco immediately. Follow these steps to remediate this vulnerability:
1. Review the Cisco Security Advisory (cisco-sa-asaftd-xss-multiple-FCB3vPZe) to identify the fixed software versions for your specific product and release train
2. Verify your current ASA or FTD software version using the 'show version' command
3. Download the appropriate fixed software version from the Cisco Software Download Center
4. Schedule a maintenance window and create a backup of your current configuration
5. Apply the software update following Cisco's upgrade procedures for your device
6. Verify the update was successful and test critical functionality
Note: Cisco has confirmed there are no workarounds available for this vulnerability. Software patching is the only effective remediation.