Cisco Secure Adaptive Security Appliance Software and Secure Firewall Threat Defense Software EIGRP Denial of Service Vulnerability

published 2026-09-16 last mo. modified 2026-09-18 last mo. also EUVD-2026-81125

cvss: 7.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 17%
public exploits: 0; none known

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.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: last mo. (2026-09-17)

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.4	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Affected products

Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
Cisco Cisco Secure Firewall Threat Defense (FTD) Software

Classification

Weakness

CWE-401 Missing Release of Memory after Effective Lifetime

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-eigrp-dos-GOhNejSj

Sources

CVE List CVE-2026-20222
NVD CVE-2026-20222

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