---
id: CVE-2025-20252
title: >-
  Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat
  Defense Software IKEv2 Denial of Service Vulnerability
summary: >-
  Multiple vulnerabilities in the Internet Key Exchange Version 2 (IKEv2)
  feature of Cisco IOS Software, Cisco IOS XE Software, Cisco Secure Firewall
  Adaptive Security Appliance (ASA) Software, and Cisco Secure Firewall Threat
  Defense (FTD) …
severity: medium
cvss: 5.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L'
cvssSource: vendor
vendor: Cisco
product: Cisco Firepower 9000 Series
affected:
  - firepower_2100_series
  - firepower_1000_series
  - asa_5500_x_series_firewalls
  - 3000_series_industrial_security_appliances_isa
  - firepower_9000_series
  - firepower_4100_series
  - secure_firewall_threat_defense_virtual
  - secure_firewall_3100_series
  - secure_firewall_4200_series
  - secure_firewall_1200_series
  - adaptive_security_virtual_appliance_asav
published: '2025-08-14'
updated: '2025-08-14'
sourceUpdated: '2025-08-14T16:00:00+00:00'
source: CSAF
sourceUrl: >-
  https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-ios-dos-DOESHWHy
references:
  - url: >-
      https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-ios-dos-DOESHWHy
  - url: 'https://software.cisco.com'
tags:
  - csaf
  - vendor-advisory
  - cisco
epss: 0.00433
epssPercentile: 0.3603
ingestedAt: '2026-10-15T11:50:11.863Z'
---

## Overview

Multiple vulnerabilities in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, Cisco IOS XE Software, Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition.

Cisco has released software updates that address these vulnerabilities. There are workarounds that address these vulnerabilities.

For more information about these vulnerabilities, see the Details ["#details"] section of this advisory.



This advisory is part of the August 2025 release of the Cisco Secure Firewall ASA, Secure FMC, and Secure FTD Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: August 2025 Semiannual Cisco Secure Firewall ASA, Secure FMC, and Secure FTD Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75415"].

## Vendor advisories

- **cisco-sa-asa-ftd-ios-dos-DOESHWHy** · Cisco · affected: Cisco Firepower 2100 Series, Cisco Firepower 1000 Series, Cisco ASA 5500-X Series Firewalls, Cisco 3000 Series Industrial Security Appliances (ISA), Cisco Firepower 9000 Series, Cisco Firepower 4100 Series, … · updated 2025-08-14 · [advisory](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-ios-dos-DOESHWHy)

**Cisco IOS, IOS XE, Secure Firewall Adaptive Security Appliance, and Secure Firewall Threat Defense Software IKEv2 Denial of Service Vulnerabilities**. Released 2025-08-14.

Affected:

- Cisco Firepower 2100 Series
- Cisco Firepower 1000 Series
- Cisco ASA 5500-X Series Firewalls
- Cisco 3000 Series Industrial Security Appliances (ISA)
- Cisco Firepower 9000 Series
- Cisco Firepower 4100 Series
- Cisco Secure Firewall Threat Defense Virtual
- Cisco Secure Firewall 3100 Series
- Cisco Secure Firewall 4200 Series
- Cisco Secure Firewall 1200 Series
- Cisco Adaptive Security Virtual Appliance (ASAv)

## Remediation

Cisco has released software updates that address this vulnerability. https://software.cisco.com