CVE-2021-34697

CVE-2021-34697 describes a denial-of-service vulnerability in Cisco IOS XE Software, specifically within its Distributed Denial of Service Attack protection feature. This flaw, stemming from incorrect programming of half-opened connection limits or TCP SYN flood/cookie features, allows an unauthenticated, remote attacker to initiate DoS attacks against or through affected devices. Rated with a CVSS score of 8.6 (High), the vulnerability is easily exploitable over the network with low attack complexity, leading to high availability impact. Currently, there is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.