Detections
Analytics
Cisco Adaptive Security Appliance (ASA) Software VPN DoS (cisco-sa-asaftd-vpn-dos-SpOFF2Re)
high Nessus Plugin ID 311455
Synopsis
The remote device is missing a vendor-supplied security patch.Description
According to its self-reported version, Cisco ASA Software is affected by a vulnerability.- A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to ineffective memory management of the VPN web server. An attacker could exploit this vulnerability by sending a large number ofcrafted HTTP requests to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. (CVE-2026-20039)
Please see the included Cisco BIDs and Cisco Security Advisory for more information.
Solution
Upgrade to the relevant fixed version referenced in Cisco bug ID CSCwo01785See Also
http://www.nessus.org/u?73afe95c
Plugin Details
Severity: High
ID: 311455
File Name: cisco-sa-asaftd-vpn-dos-SpOFF2Re-asa.nasl
Version: 1.1
Type: Local
Family: CISCO
Published: 5/1/2026
Updated: 5/1/2026
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.4
CVSS v2
Risk Factor: High
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
CVSS Score Source: CVE-2026-20039
CVSS v3
Risk Factor: High
Base Score: 8.6
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Vulnerability Information
CPE: cpe:/a:cisco:adaptive_security_appliance_software
Required KB Items: Host/Cisco/ASA
Patch Publication Date: 3/4/2026
Vulnerability Publication Date: 3/4/2026
Reference Information
CVE: CVE-2026-20039