CVE-2023-20256

Severity: medium (CVSS 5.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-11-01 · updated 2026-08-11
Weakness: CWE-290

Description

Multiple vulnerabilities in the per-user-override 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. These vulnerabilities are due to a logic error that could occur when the affected software constructs and applies per-user-override rules. An attacker could exploit these vulnerabilities by connecting to a network through an affected device that has a vulnerable configuration. A successful exploit could allow the attacker to bypass the interface ACL and access resources that would should be protected.

Affected products

Cisco ASA Software: 9.8.4.22, 9.8.4.25, 9.8.4.26, 9.8.4.29, 9.8.4.32, 9.8.4.33 (+103)
Cisco Firepower Threat Defense Software: 6.2.3.16, 6.2.3.17, 6.2.3.18, 6.4.0.10, 6.4.0.11, 6.4.0.12 (+37)

References

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