The vulnerability, tracked as CVE-2026–76418, is rated 8.6 on the CVSS scoring system. Successful exploitation could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial-of-service (DoS) condition.

According to Cisco, the issue is rooted in the Remote Access SSL VPN service of ASA and FTD software.

“This vulnerability is due to logic errors when secondary authentication is configured on a tunnel group,” it said in a Wednesday advisory. “An attacker could exploit this vulnerability by sending a crafted request when connecting to the SSL remote access VPN. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.”