Description
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.
Affected products
cisco: adaptive security appliance software; cisco: secure firewall threat defense
References1
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Vendor Advisory
Metrics
- CVSS 3.1
-
5.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 40 · as of 6 November 2026
- CWE
- CWE-290
Could this be exploited in your environment?
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