High severity · published Oct 28, 2026
CVE-2026-76418
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Tunnel Denial of Service Vulnerability
New
8.6
CVSS
–
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CS
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · Cisco
9.16.1; 9.16.1.28; 9.16.2; 9.16.2.3; 9.16.2.7; 9.16.2.11; +34 more · source: vendor
CS
Cisco Secure Firewall Threat Defense (FTD) Software · Cisco
7.0.0; 7.0.0.1; 7.0.1; 7.0.1.1; 7.0.2; 7.2.0; +34 more · source: vendor
Affected product
CS
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
Cisco
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-76418
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-76418
sec.cloudapps.cisco.com
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-tunnel-dos-s6mgkb75
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