CVE-2026-76418 Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability

Added to the CISA Known Exploited Vulnerabilities catalog on 2026-10-29. This vulnerability is known to be actively exploited.

Vendor / product: Cisco Secure Firewall ASA Software and Cisco Secure FTD Software

Cisco Secure Firewall ASA Software and Cisco Secure FTD Software contains an unchecked return value to NULL pointer dereference vulnerability that could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.

Required action: Apply 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.

Due date: 2026-11-01

Known ransomware campaign use: Unknown