HIGH · CVSS 8.6
ACTIVELY EXPLOITED
PATCH AVAILABLE
CVE-2026-76418: Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability
| Vendor | Cisco |
|---|---|
| Product | Secure Firewall ASA Software and Cisco Secure FTD Software |
| CVSS score | 8.6 · CVSS 3.1 · HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| EPSS | 0.8% (percentile 58) |
| Actively exploited | Yes, according to CISA KEV |
| Added to CISA KEV | 29 Oct 2026 |
| CISA federal deadline | 1 Nov 2026 |
| Weakness (CWE) | CWE-690 |
| NVD published | 28 Oct 2026 |
| NVD last modified | 30 Oct 2026 |
| NVD status | Analyzed |
Affected versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Cisco Secure Firewall Threat Defense | from 10.0.0 before 10.0.3 | 10.0.3 |
| Cisco Secure Firewall Threat Defense | before 7.0.11 | 7.0.11 |
| Cisco Secure Firewall Threat Defense | from 7.2.0 before 7.2.13 | 7.2.13 |
| Cisco Secure Firewall Threat Defense | from 7.3.0 before 7.4.9 | 7.4.9 |
| Cisco Secure Firewall Threat Defense | from 7.7.0 before 7.7.14 | 7.7.14 |
| Cisco Secure Firewall Threat Defense | from 7.6.0 up to 7.6.7 | – |
| Cisco Secure Firewall Threat Defense | 10.1.0 | – |
| Cisco Adaptive Security Appliance Software | before 9.16.4.104 | 9.16.4.104 |
| Cisco Adaptive Security Appliance Software | from 9.18 before 9.18.4.96 | 9.18.4.96 |
| Cisco Adaptive Security Appliance Software | from 9.19 before 9.20.4.50 | 9.20.4.50 |
| Cisco Adaptive Security Appliance Software | from 9.22 before 9.22.3.200 | 9.22.3.200 |
| Cisco Adaptive Security Appliance Software | from 9.23 before 9.23.1.48 | 9.23.1.48 |
| Cisco Adaptive Security Appliance Software | from 9.24.1 before 9.24.1.27 | 9.24.1.27 |
| Cisco Adaptive Security Appliance Software | 9.24.10 | – |
Required action (CISA's text)
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.
Description (NVD)
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.
Vendor advisories
- Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Tunnel Denial of Service Vulnerability
- Kwetsbaarheid verholpen in Cisco Secure Firewall ASA en FTD Software
SOURCES
Other Cisco flaws
- CVE-2026-20320: Cisco BroadWorks Improper Restriction of XML External Entity Reference Vulnerability
- CVE-2026-76519: Cisco Secure Email Gateway Relative Path Traversal Vulnerability
- CVE-2026-76504: Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability
- CVE-2026-76460: Cisco Identity Services Engine Incorrect Use of Privileged APIs Vulnerability
- CVE-2026-76461: Cisco Secure Email Gateway SQL Injection Vulnerability
Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 30 Oct 2026.