TL;DR 📌

A medium severity vulnerability has been identified in Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Software, allowing unauthenticated remote attackers to bypass access control rules for loopback interfaces. No workarounds are available, and software updates are necessary to mitigate the risk.

What happened 🕵️‍♂️

Cisco has disclosed a vulnerability in the access control rules implementation for loopback interfaces in its Secure Firewall ASA and FTD Software. This flaw could enable an unauthenticated remote attacker to send traffic that should be blocked to a loopback interface, effectively bypassing configured access control rules. The vulnerability arises from improper enforcement of these rules, posing a potential risk to network security.