CVE-2026-20049

Insufficient Memory Allocation in IKEv2 GCM Decryption Causes DoS on Cisco ASA/FTD

Published Mar 4, 2026 CVSS 3.1 · 7.7 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:* cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*
Vendors & Products Cisco firepower Threat Defense Software
Type Values Removed Values Added
Title Insufficient Memory Allocation in IKEv2 GCM Decryption Causes DoS on Cisco ASA/FTD
Type Values Removed Values Added
First Time appeared Cisco firepower Threat Defense Software
CPEs cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
Vendors & Products Cisco firepower Threat Defense Software
Type Values Removed Values Added
First Time appeared Cisco
Cisco adaptive Security Appliance Software
Cisco secure Firewall Threat Defense
Vendors & Products Cisco
Cisco adaptive Security Appliance Software
Cisco secure Firewall Threat Defense
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Weaknesses CWE-131
References
Metrics cvssV3_1

{'score': 7.7, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
cisco
Published
Updated
Mar 4, 2026, 8:55 PM
Reserved
Oct 8, 2025, 11:59 AM
Status
Analyzed
Published
Mar 4, 2026, 6:16 PM
Modified
Aug 11, 2026, 7:40 PM