TL;DR 📌

A medium-severity vulnerability has been identified in Cisco IOS XE SD-WAN Software that allows unauthenticated remote attackers to bypass Layer 3 and Layer 4 traffic filters. This could lead to unauthorized access to network resources. Users are advised to implement workarounds or upgrade to fixed software versions as soon as possible.

What happened 🕵️‍♂️

A vulnerability in the packet filtering features of Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to bypass Layer 3 and Layer 4 traffic filters. This issue arises from improper traffic filtering conditions on affected devices. By sending a crafted packet, an attacker could exploit this vulnerability to inject malicious packets into the network. Proof-of-concept exploit code is available, although there are no known instances of malicious exploitation at this time.