High severity · published Mar 4, 2026
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…
7.7
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CS
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · Cisco
9.12.4.7; 9.12.4.10; 9.12.4.13; 9.12.4.8; 9.12.4.18; 9.12.4.24; +34 more · source: vendor
CS
Cisco Secure Firewall Threat Defense (FTD) Software · Cisco
6.4.0.10; 6.4.0.11; 6.4.0.12; 6.4.0.13; 6.4.0.14; 6.4.0.15; +34 more · source: vendor
AS
Adaptive Security Appliance Software · Cisco
9.18.1 before 9.18.4.66; 9.19.1 before 9.20.3.20; 9.22.1.1 before 9.22.2.4; 9.23.1 before 9.23.1.3 · source: NVD
SF
Secure Firewall Threat Defense · Cisco
7.2.0 before 7.2.11; 7.3.0 before 7.4.3; 7.6.0 before 7.6.4; 7.7.0 before 7.7.10 · source: NVD
Affected product
CS
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
Cisco
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