A vulnerability in the Network Service Group (NSG) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat D…

published 2024-10-23 2y ago modified 2026-08-11 3mo ago also EUVD-2024-18099

cvss: 5.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 39%
public exploits: 0; none known

A vulnerability in the Network Service Group (NSG) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass a configured access control list (ACL) and allow traffic that should be denied to flow through an affected device. This vulnerability is due to a logic error that occurs when NSG ACLs are populated on an affected device. An attacker could exploit this vulnerability by establishing a connection to the affected device. A successful exploit could allow the attacker to bypass configured ACL rules.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 2y ago (2024-10-23)

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Affected products

Cisco Cisco Adaptive Security Appliance (ASA) Software
Cisco Cisco Firepower Threat Defense Software
cisco adaptive_security_appliance
cisco firepower_threat_defense_software

Classification

Weakness

CWE-290 Authentication Bypass by Spoofing

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-nsgacl-bypass-77XnEAsL
vendor-advisory

Sources

CVE List CVE-2024-20384
NVD CVE-2024-20384

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