A vulnerability in the Remote Access SSL VPN service of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to logic errors when secondary authentication is configured on a tunnel group. An attacker could exploit this vulnerability by sending a crafted request when connecting to the SSL remote access VPN. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.
High 8.6Actively exploited
CVE-2026-76418
Cisco Secure Firewall ASA Software and Cisco Secure FTD Software — Unchecked Return Value to NULL Pointer Dereference.
A vulnerability in the Remote Access SSL VPN service of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote…
WeaknessCWE-690
Published Updated Source NVD and CISA KEV
CVSS 3.1
8.6
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Exploit chance, 30 days
0.8%
Higher than 57% of all CVEs (EPSS)
Status
Actively exploited
On CISA KEV since 29 Oct 2026
Patch
Unknown
Check the vendor advisory
What happened
What to do
- 01Check whether you run Cisco Secure Firewall ASA Software and Cisco Secure FTD Software, and which version.
- 02Follow the vendor advisory for a fix or a workaround.
- 03Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA deadlineUS federal agencies must remediate by
References
Timeline · UTC
- Published to NVD
- Added to CISA KEV
- NVD record updated
- CISA remediation deadline
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