Vulnerability · Published Mar 4, 2026 · Assigned by cisco
CVE-2026-20100
High 7.7
In plain English
A high-severity buffer overflow in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities).
Official description
A vulnerability in the LUA interperter of the Remote Access SSL VPN feature of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker with a valid VPN connection to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This does not affect the management or MUS interfaces. This vulnerability is due to trusting user input without validation in the LUA interprerter. An attacker could exploit this vulnerability by sending crafted HTTP packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | 9.12.19.12.1.29.12.1.39.12.29.12.2.49.12.2.59.12.2.99.12.3 |
| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | 6.4.06.4.0.16.4.0.36.4.0.26.4.0.46.4.0.56.4.0.66.4.0.7 |
Weakness: CWE-120 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H