CVE-2026-20049

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 C

Severity
High 7.7
CVSS 3.1
Exploited
Not listed
EPSS
0.003
21.4th percentile
Discovered by
Vendor
Published by the vendor
Published
Mar 4, 2026
Assigned by cisco

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.

Weakness: CWE-131

Affected products

Vendor Product Category Matched by
Cisco Cisco Adaptive Security Appliance (ASA) Firewall / NGFW cna-assigner
Cisco Cisco Secure Firewall Firewall / NGFW cna-assigner
Vendor-reported affected versions (2)
  • Cisco · Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
  • Cisco · Cisco Secure Firewall Threat Defense (FTD) Software