CVE-2019-15261

CVE-2019-15261 is a denial-of-service vulnerability in Cisco Aironet Access Points (APs) affecting models such as the 1810, 1830, and 1850 series. An unauthenticated, remote attacker can exploit insufficient validation of Generic Routing Encapsulation (GRE) frames within the Point-to-Point Tunneling Protocol (PPTP) VPN packet processing functionality. This allows an attacker to cause an affected AP to reload, leading to a denial of service for connected clients. With a CVSS score of 8.6 (HIGH), this vulnerability has a network attack vector, low attack complexity, and high impact on availability. There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage.