Skip to content
NewA calmer, faster ZeroHour
Advisorymedium

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authentication Denial of Service Vulnerability

Cisco Security Advisories ()2 · 1 read
Part of a story covered by 15 sourcesCisco Secure Firewall Adaptive Security Appliance, Secure Firewall Threat Defense, and Secure Firewall Management Center Software Hardening Release: September 2026Merged summary & timeline
AI summary · glm-5.3-flashSummaries by Vani AI

Cisco patched an ASA/FTD IKEv2 certificate authentication flaw letting unauthenticated remote attackers crash the IKEv2 process and reload devices with crafted certificates.

A logic error during the certificate authentication phase of IKEv2 connection setup in Cisco Secure Firewall ASA and FTD Software allows an unauthenticated, remote attacker to crash the IKEv2 process. Exploitation involves attempting to establish an IKEv2 VPN connection with a crafted certificate, causing a denial of service through an unexpected device reload. Cisco has released software updates.

Key facts
  • Logic error in IKEv2 certificate authentication phase of connection setup
  • Crafted certificate during VPN setup crashes the IKEv2 process
  • Successful exploit causes unexpected device reload and denial of service
  • Cisco has released software updates
Analyze this story with Vani AIImpact, who is affected and what defenders should do, in a new chat

From the original article

A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly.

Cisco Security Advisories

sec.cloudapps.cisco.com

Read the full article at Cisco Security Advisories

A short excerpt; the article and its images belong to the publisher. Summary, key facts and assessment above are AI-written from the article and can be wrong.