High severity · published Sep 16, 2026
CVE-2026-20222
Cisco Secure Adaptive Security Appliance Software and Secure Firewall Threat Defense Software EIGRP Denial of Service Vulnerability
7.4
CVSS
0.3%
EPSS
No
On KEV
Description
A vulnerability in the EIGRP implementation in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, adjacent attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.
This vulnerability is due to improper resource management when handling EIGRP update messages. An attacker could exploit this vulnerability by sending crafted EIGRP updates at a high rate to an affected device. A successful exploit could allow the attacker to trigger a memory leak that will eventually cause the affected device to reload unexpectedly.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 17% 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
9.19.1; 9.19.1.5; 9.19.1.9; 9.19.1.12; 9.19.1.18; 9.20.1; +34 more · source: vendor
CS
Cisco Secure Firewall Threat Defense (FTD) Software · Cisco
7.3.0; 7.3.1; 7.3.1.1; 7.4.0; 7.4.1; 7.4.1.1; +19 more · source: vendor
Affected product
CS
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
Cisco
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-20222
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-20222
sec.cloudapps.cisco.com
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-eigrp-dos-GOhNejSj
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