CVE-2026-20103
Last modified
CVE-2026-20103 is a high-severity vulnerability rated 8.6/10 on the CVSS scale. 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. EPSS estimates a 0.35% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Adaptive Security Appliance Software | >= 9.12.1, < 9.16.4.85 |
| Cisco | Adaptive Security Appliance Software | >= 9.17.1, < 9.18.4.66 |
| Cisco | Adaptive Security Appliance Software | >= 9.19.1, < 9.20.4 |
| Cisco | Adaptive Security Appliance Software | >= 9.22.1.1, < 9.22.2.4 |
| Cisco | Adaptive Security Appliance Software | >= 9.23.1, < 9.23.1.7 |
| Cisco | Secure Firewall Threat Defense | >= 6.4.0, < 7.0.9 |
| Cisco | Secure Firewall Threat Defense | >= 7.1.0, < 7.2.11 |
| Cisco | Secure Firewall Threat Defense | >= 7.3.0, < 7.4.3 |
| Cisco | Secure Firewall Threat Defense | >= 7.6.0, < 7.6.4 |
| Cisco | Secure Firewall Threat Defense | >= 7.7.0, < 7.7.11 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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