vulnerability

Cisco FTD: CVE-2022-20795: Cisco Adaptive Security Appliance and Cisco Firepower Threat Defense Software AnyConnect SSL VPN Denial of Service Vulnerability

Severity
5
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:P)
Published
Apr 20, 2022
Added
Jan 29, 2025
Modified
Mar 31, 2026

Description

A vulnerability in the implementation of the Datagram TLS (DTLS) protocol in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause high CPU utilization, resulting in a denial of service (DoS) condition. This vulnerability is due to suboptimal processing that occurs when establishing a DTLS tunnel as part of an AnyConnect SSL VPN connection. An attacker could exploit this vulnerability by sending a steady stream of crafted DTLS traffic to an affected device. A successful exploit could allow the attacker to exhaust resources on the affected VPN headend device. This could cause existing DTLS tunnels to stop passing traffic and prevent new DTLS tunnels from establishing, resulting in a DoS condition. Note: When the attack traffic stops, the device recovers gracefully.

Solution

cisco-ftd-upgrade-latest
Title
Rapid7 Labs

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