CVE-2026-76418: Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on , 1 day after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 0.6%
EPSS score, percentile 47.3 of all scored records
- How severe?
- 8.6 High
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline . Apply mitigations in accordance with vendor instructions … Full text
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 9.16.1
- 9.16.1.28
- 9.16.2
- 9.16.2.3
- 9.16.2.7
- 9.16.2.11
and 18 more in the table below
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Required action, set by CISA
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.
CISA due date for this action: .
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-tunnel-dos-s6mgkb75
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- https://nvd.nist.gov/vuln/detail/CVE-2026-76418
This summary is based on CISA's catalog entry and the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 9.16.1 |
| Affected | 9.16.1.28 |
| Affected | 9.16.2 |
| Affected | 9.16.2.3 |
| Affected | 9.16.2.7 |
| Affected | 9.16.2.11 |
| Affected | 9.16.2.13 |
| Affected | 9.16.2.14 |
| Affected | 9.16.3.3 |
| Affected | 9.16.3 |
| Affected | 9.16.3.14 |
| Affected | 9.18.1 |
Versions not listed are: unknown.
And 130 more version entries in the CVE record.
| Status | Versions |
|---|---|
| Affected | 7.0.0 |
| Affected | 7.0.0.1 |
| Affected | 7.0.1 |
| Affected | 7.0.1.1 |
| Affected | 7.0.2 |
| Affected | 7.2.0 |
| Affected | 7.0.2.1 |
| Affected | 7.0.3 |
| Affected | 7.2.0.1 |
| Affected | 7.0.4 |
| Affected | 7.2.1 |
| Affected | 7.0.5 |
Versions not listed are: unknown.
And 55 more version entries in the CVE record.
Source: CVE List, as of . About the data.
About this vulnerability
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.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2026-76418 to its Known Exploited Vulnerabilities (KEV) catalog on 29 Oct 2026.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 1 Nov 2026.
- The CVE record was published on 28 Oct 2026, 1 day before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 8.6 (High), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.6% (percentile 47.3), as of 29 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact partial.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Tunnel Denial of Service Vulnerability
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.
Source: CVE List, as of . About the data.
Weakness
CWE-690
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated | |
| Added to CISA KEV | |
| CISA due date for the required action |
References
1
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