Vulnerability Description
A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust device memory resulting in a denial of service (DoS) condition to new Remote Access SSL VPN connections. This does not affect the management interface, though it may become temporarily unresponsive. This vulnerability is due to trusting user input without validation. An attacker could exploit this vulnerability by sending crafted packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device web interface to stop responding, resulting in a DoS condition.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Adaptive Security Appliance Software | >= 9.12.1, < 9.16.4.85 |
| Cisco | Firepower Threat Defense Software | >= 6.4.0, < 7.0.9 |
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-20103?
CVE-2026-20103 is a vulnerability with a CVSS score of 8.6 (HIGH). A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthen...
How severe is CVE-2026-20103?
CVE-2026-20103 has been rated HIGH with a CVSS base score of 8.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-20103?
Check the references section above for vendor advisories and patch information. Affected products include: Cisco Adaptive Security Appliance Software, Cisco Firepower Threat Defense Software.