A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive… (CVE-2026-20249)
A logic error in the certification authentication feature of IKEv2 on Cisco Secure Firewall ASA and FTD software allows an unauthenticated remote attacker to cause the device to reload unexpectedly. Exploitation involves sending a crafted certificate during the IKEv2 VPN connection setup, leading to a denial of service by crashing the IKEv2 process.
AI Analysis
Technical Summary
CVE-2026-20249 is a vulnerability in the certification authentication phase of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) and Threat Defense (FTD) software. The flaw is a logic error that can be triggered by an unauthenticated remote attacker sending a crafted certificate during IKEv2 VPN connection setup. Successful exploitation causes the IKEv2 process to crash, resulting in a denial of service condition by forcing the affected device to reload unexpectedly.
Potential Impact
The vulnerability allows an unauthenticated remote attacker to cause a denial of service by crashing the IKEv2 process, which leads to the affected Cisco firewall device reloading unexpectedly. There is no impact on confidentiality or integrity according to the CVSS vector. The primary impact is availability disruption.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround information is provided in the available data.
A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive… (CVE-2026-20249)
Description
A logic error in the certification authentication feature of IKEv2 on Cisco Secure Firewall ASA and FTD software allows an unauthenticated remote attacker to cause the device to reload unexpectedly. Exploitation involves sending a crafted certificate during the IKEv2 VPN connection setup, leading to a denial of service by crashing the IKEv2 process.
CVSS v3.1
Score 8.6high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-20249 is a vulnerability in the certification authentication phase of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) and Threat Defense (FTD) software. The flaw is a logic error that can be triggered by an unauthenticated remote attacker sending a crafted certificate during IKEv2 VPN connection setup. Successful exploitation causes the IKEv2 process to crash, resulting in a denial of service condition by forcing the affected device to reload unexpectedly.
Potential Impact
The vulnerability allows an unauthenticated remote attacker to cause a denial of service by crashing the IKEv2 process, which leads to the affected Cisco firewall device reloading unexpectedly. There is no impact on confidentiality or integrity according to the CVSS vector. The primary impact is availability disruption.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround information is provided in the available data.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-q3fg-q5c4-7677
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-20249"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aab49a355bf5e2cf5992074
Added to database: 09/17/2026, 02:00:03 UTC
Last enriched: 09/17/2026, 02:38:49 UTC
Last updated: 09/17/2026, 05:41:29 UTC
Views: 3
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