CVE-2022-20742

CVE-2022-20742 is a high-severity vulnerability in the IPsec VPN library of Cisco ASA and FTD Software, stemming from improper GCM cipher implementation. An unauthenticated, remote attacker in a man-in-the-middle position could exploit this by intercepting sufficient encrypted messages to decrypt, read, modify, and re-encrypt data within an IPsec IKEv2 VPN tunnel. The attack complexity is high, but a successful exploit leads to complete confidentiality and integrity compromise of tunnel data. There is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this vulnerability.