Vulnerability · Published Mar 4, 2026 · Assigned by cisco
CVE-2026-20049
High 7.7
In plain English
A high-severity security flaw 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 27% of all known vulnerabilities).
Official description
A vulnerability in the processing of Galois/Counter Mode (GCM)-encrypted Internet Key Exchange version 2 (IKEv2) IPsec traffic of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to the allocation of an insufficiently sized block of memory. An attacker could exploit this vulnerability by sending crafted GCM-encrypted IPsec traffic to an affected device. A successful exploit could allow the attacker to cause an unexpected reload of the device, resulting in a DoS condition. To exploit this vulnerability, the attacker must have valid credentials to establish a VPN connection with the affected device.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | 9.12.4.79.12.4.109.12.4.139.12.4.89.12.4.189.12.4.249.12.4.269.12.4.29 |
| Cisco | Cisco Secure Firewall Threat Defense (FTD) Software | 6.4.0.106.4.0.116.4.0.126.4.0.136.4.0.146.4.0.156.4.0.166.4.0.17 |
Weakness: CWE-131 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H