CVE-2026-20014
📋 TL;DR
This vulnerability in Cisco Secure Firewall ASA and FTD software allows authenticated VPN users to send specially crafted IKEv2 packets that cause memory exhaustion, leading to device reload and denial of service. The DoS condition can affect not only the vulnerable device but also other network services. Organizations using affected Cisco firewall products with IKEv2 VPN enabled are at risk.
💻 Affected Systems
- Cisco Secure Firewall ASA Software
- Cisco Secure FTD Software
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete network disruption as firewall reloads, potentially affecting all traffic passing through the device and causing cascading failures in dependent systems.
Likely Case
Intermittent firewall outages requiring manual intervention, VPN connectivity loss, and degraded network performance during reload cycles.
If Mitigated
Minimal impact if proper network segmentation, monitoring, and access controls limit VPN user access to trusted entities only.
🎯 Exploit Status
Requires valid VPN credentials and knowledge of IKEv2 protocol manipulation. Attack surface limited to VPN endpoints.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Cisco advisory for specific fixed releases
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ikev2-dos-eBueGdEG
Restart Required: Yes
Instructions:
1. Review Cisco advisory for exact fixed versions. 2. Download appropriate software update from Cisco. 3. Schedule maintenance window. 4. Backup configuration. 5. Apply update following Cisco upgrade procedures. 6. Verify functionality post-update.
🔧 Temporary Workarounds
Disable IKEv2 VPN
allTemporarily disable IKEv2 VPN functionality if not required
crypto ikev2 enable outside client-services port 443
no crypto ikev2 enable
Restrict VPN Access
allLimit VPN access to trusted IP ranges and implement strict authentication
access-list VPN-ACL extended permit ip host [trusted-ip] any
tunnel-group [group] general-attributes
address-pool [pool]
ip-local-pool [pool] [range]
🧯 If You Can't Patch
- Implement strict VPN user access controls and monitoring
- Deploy network segmentation to limit blast radius of potential DoS
🔍 How to Verify
Check if Vulnerable:
Check ASA/FTD version and IKEv2 configuration: 'show version' and 'show running-config crypto ikev2'Check Version:
show version | include VersionVerify Fix Applied:
Verify updated version: 'show version' and test IKEv2 VPN connectivity📡 Detection & Monitoring
Log Indicators:
- Memory exhaustion warnings
- Unexpected device reloads
- IKEv2 authentication failures
- High CPU/memory utilization spikes
Network Indicators:
- Unusual IKEv2 packet patterns
- VPN connection floods
- Firewall becoming unresponsive
SIEM Query:
source="cisco-asa" AND ("%ASA-3-325002" OR "%ASA-6-302013" OR "%ASA-4-722041") AND "IKEv2"