CVE-2026-20249Disclosure

LOWCVSS 8.6 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch affected systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

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. This vulnerability is due to a logic error during the certificate authentication phase of the IKEv2 connection setup. An attacker could exploit this vulnerability by attempting to establish an IKEv2 VPN connection with a crafted certificate. A successful exploit could allow the attacker to cause the IKEv2 process to crash, causing a denial of service (DoS) condition.

0.5/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-704

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

STABLE

Threat summary

  • Patch or workaround signal is available
  • 2 mentions across 2 observed days
  • Momentum state: stable

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 2 signals
  • Disclosure: 1 classified signal
  • Peaked 1d ago at 1 mentions (2026-09-16); latest day: 1
  • 2 total mentions across 2 days

Deep dive

Activity timeline2 mentions / 2d
00111Mentions · 2026-09-16: 1Mentions · 2026-10-02: 1Patch / Workaround · 2026-10-02: 1Technical Details · 2026-09-16: 1Technical Details · 2026-10-02: 109-1610-02
Signal classification2 categories
Disclosure
150.0%
Patch
150.0%
Referenced assets1 URL
By indicator
Classification over time
DateTotalLabels
2026-09-161
Disclosure1
2026-10-021
Patch1
Full discourse2 posts
  • DFIR Lab@DFIR_Lab
    Patch

    🚨 HIGH: CVE-2026-20249 (CVSS 8.6) - Cisco ASA/FTD IKEv2 DoS vulnerability. Unauthenticated remote attackers can crash devices via crafted certificates during VPN setup. Patch immediately. #CVE #Vulnerability #PatchNow #CyberSecurity https://t.co/C1nvUKdw3y

    Post summary

    The tweet highlights a high‑severity DoS vulnerability in Cisco ASA/FTD IKEv2 (CVE-2026-20249, CVSS 8.6) and urges immediate patching, while also describing the unauthenticated remote attack vector.

    0000049
    144 followersView on X
  • Kaitan ID Security@KaitanSecurity
    Disclosure

    ⚠️ HIGH — CVE-2026-20249 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authent… CVSS 8.6 Full analysis → https://sec.kaitan.id/cves/CVE-2026-20249 #Cisco #CyberSecurity #InfoSec

    Post summary

    The tweet flags a high‑severity CVE–2026‒0249 affecting Cisco Secure Firewall Adaptive Security Appliance and Threat Defense software, focusing on IKEv2 certificate authentication, with a CVSS score of 8.6, and provides a link to a full analysis but does not discuss a PoC, exploit, patch, or active exploitation.

    0000041
    90 followersView on X

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