Cisco Firepower Threat Defense (FTD) Software ESP Packet Processing DoS (cisco-sa-asaftd-esp-dos-uv7yD8P5)

high Nessus Plugin ID 311443

Synopsis

The remote device is missing a vendor-supplied security patch.

Description

According to its self-reported version, Cisco Secure Firewall Threat Defense (FTD) Software is affected by a vulnerability.

- A vulnerability in the processing of Galois/Counter Mode (GCM)-encrypted Internet Key Exchange version 2 (IKEv2) IPsec traffic of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to the allocation of an insufficiently sized block of memory. An attacker could exploit this vulnerability by sending crafted GCM- encrypted IPsec traffic to an affected device. A successful exploit could allow the attacker to cause an unexpected reload of the device, resulting in a DoS condition. To exploit this vulnerability, the attacker must have valid credentials to establish a VPN connection with the affected device. (CVE-2026-20049)

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 CSCwo40957

Plugin Details

Severity: High

ID: 311443

File Name: cisco-sa-asaftd-esp-dos-uv7yD8P5-ftd.nasl

Version: 1.1

Type: Combined

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: Medium

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:C

CVSS Score Source: CVE-2026-20049

CVSS v3

Risk Factor: High

Base Score: 7.7

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Vulnerability Information

CPE: cpe:/o:cisco:firepower_threat_defense

Required KB Items: installed_sw/Cisco Firepower Threat Defense

Patch Publication Date: 3/4/2026

Vulnerability Publication Date: 3/4/2026

Reference Information

CVE: CVE-2026-20049

CISCO-SA: cisco-sa-asaftd-esp-dos-uv7yD8P5

IAVA: 2026-A-0201

CISCO-BUG-ID: CSCwo40957

Detections

Analytics