medium
5.8
CWE
290
Advisory Published
Updated

CVE-2023-20256

First published: Wed Nov 01 2023(Updated: )

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.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco Adaptive Security Appliance=9.8.4.22
Cisco Adaptive Security Appliance=9.8.4.25
Cisco Adaptive Security Appliance=9.8.4.26
Cisco Adaptive Security Appliance=9.8.4.29
Cisco Adaptive Security Appliance=9.8.4.32
Cisco Adaptive Security Appliance=9.8.4.33
Cisco Adaptive Security Appliance=9.8.4.34
Cisco Adaptive Security Appliance=9.8.4.35
Cisco Adaptive Security Appliance Software=9.8.4.39
Cisco Adaptive Security Appliance Software=9.8.4.40
Cisco Adaptive Security Appliance Software=9.8.4.41
Cisco Adaptive Security Appliance Software=9.8.4.43
Cisco Adaptive Security Appliance Software=9.8.4.44
Cisco Adaptive Security Appliance Software=9.8.4.45
Cisco Adaptive Security Appliance Software=9.8.4.46
Cisco Adaptive Security Appliance Software=9.8.4.48
Cisco Adaptive Security Appliance Software=9.12.4.2
Cisco Adaptive Security Appliance Software=9.12.4.4
Cisco Adaptive Security Appliance Software=9.12.4.7
Cisco Adaptive Security Appliance Software=9.12.4.8
Cisco Adaptive Security Appliance Software=9.12.4.10
Cisco Adaptive Security Appliance Software=9.12.4.13
Cisco Adaptive Security Appliance Software=9.12.4.18
Cisco Adaptive Security Appliance Software=9.12.4.24
Cisco Adaptive Security Appliance Software=9.12.4.26
Cisco Adaptive Security Appliance Software=9.12.4.29
Cisco Adaptive Security Appliance Software=9.12.4.30
Cisco Adaptive Security Appliance Software=9.12.4.35
Cisco Adaptive Security Appliance Software=9.12.4.37
Cisco Adaptive Security Appliance Software=9.12.4.38
Cisco Adaptive Security Appliance Software=9.12.4.39
Cisco Adaptive Security Appliance Software=9.12.4.40
Cisco Adaptive Security Appliance Software=9.12.4.41
Cisco Adaptive Security Appliance Software=9.12.4.47
Cisco Adaptive Security Appliance Software=9.12.4.48
Cisco Adaptive Security Appliance Software=9.12.4.50
Cisco Adaptive Security Appliance Software=9.12.4.52
Cisco Adaptive Security Appliance Software=9.12.4.54
Cisco Adaptive Security Appliance Software=9.12.4.55
Cisco Adaptive Security Appliance Software=9.12.4.56
Cisco Adaptive Security Appliance Software=9.14.1.10
Cisco Adaptive Security Appliance Software=9.14.1.15
Cisco Adaptive Security Appliance Software=9.14.1.19
Cisco Adaptive Security Appliance Software=9.14.1.30
Cisco Adaptive Security Appliance Software=9.14.2
Cisco Adaptive Security Appliance Software=9.14.2.4
Cisco Adaptive Security Appliance Software=9.14.2.8
Cisco Adaptive Security Appliance Software=9.14.2.13
Cisco Adaptive Security Appliance Software=9.14.2.15
Cisco Adaptive Security Appliance Software=9.14.3
Cisco Adaptive Security Appliance Software=9.14.3.1
Cisco Adaptive Security Appliance Software=9.14.3.9
Cisco Adaptive Security Appliance Software=9.14.3.11
Cisco Adaptive Security Appliance Software=9.14.3.13
Cisco Adaptive Security Appliance Software=9.14.3.15
Cisco Adaptive Security Appliance Software=9.14.3.18
Cisco Adaptive Security Appliance Software=9.14.4
Cisco Adaptive Security Appliance Software=9.14.4.6
Cisco Adaptive Security Appliance Software=9.14.4.7
Cisco Adaptive Security Appliance Software=9.14.4.12
Cisco Adaptive Security Appliance Software=9.14.4.13
Cisco Adaptive Security Appliance Software=9.14.4.14
Cisco Adaptive Security Appliance Software=9.14.4.15
Cisco Adaptive Security Appliance Software=9.14.4.17
Cisco Adaptive Security Appliance Software=9.14.4.22
Cisco Adaptive Security Appliance Software=9.14.4.23
Cisco Adaptive Security Appliance Software=9.15.1
Cisco Adaptive Security Appliance Software=9.15.1.1
Cisco Adaptive Security Appliance Software=9.15.1.7
Cisco Adaptive Security Appliance Software=9.15.1.10
Cisco Adaptive Security Appliance Software=9.15.1.15
Cisco Adaptive Security Appliance Software=9.15.1.16
Cisco Adaptive Security Appliance Software=9.15.1.17
Cisco Adaptive Security Appliance Software=9.15.1.21
Cisco Adaptive Security Appliance Software=9.16.1
Cisco Adaptive Security Appliance Software=9.16.1.28
Cisco Adaptive Security Appliance Software=9.16.2
Cisco Adaptive Security Appliance Software=9.16.2.3
Cisco Adaptive Security Appliance Software=9.16.2.7
Cisco Adaptive Security Appliance Software=9.16.2.11
Cisco Adaptive Security Appliance Software=9.16.2.13
Cisco Adaptive Security Appliance Software=9.16.2.14
Cisco Adaptive Security Appliance Software=9.16.3
Cisco Adaptive Security Appliance Software=9.16.3.3
Cisco Adaptive Security Appliance Software=9.16.3.14
Cisco Adaptive Security Appliance Software=9.16.3.15
Cisco Adaptive Security Appliance Software=9.16.3.19
Cisco Adaptive Security Appliance Software=9.16.3.23
Cisco Adaptive Security Appliance Software=9.16.4
Cisco Adaptive Security Appliance Software=9.16.4.9
Cisco Adaptive Security Appliance Software=9.16.4.14
Cisco Adaptive Security Appliance Software=9.17.1
Cisco Adaptive Security Appliance Software=9.17.1.7
Cisco Adaptive Security Appliance Software=9.17.1.9
Cisco Adaptive Security Appliance Software=9.17.1.10
Cisco Adaptive Security Appliance Software=9.17.1.11
Cisco Adaptive Security Appliance Software=9.17.1.13
Cisco Adaptive Security Appliance Software=9.17.1.15
Cisco Adaptive Security Appliance Software=9.17.1.20
Cisco Adaptive Security Appliance Software=9.17.1.30
Cisco Adaptive Security Appliance Software=9.18.1
Cisco Adaptive Security Appliance Software=9.18.1.3
Cisco Adaptive Security Appliance Software=9.18.2
Cisco Adaptive Security Appliance Software=9.18.2.5
Cisco Adaptive Security Appliance Software=9.18.2.7
Cisco Adaptive Security Appliance Software=9.18.2.8
Cisco Adaptive Security Appliance Software=9.18.3
Cisco Adaptive Security Appliance Software=9.19.1
Cisco Adaptive Security Appliance Software=9.19.1.5
Cisco Firepower Threat Defense=6.2.3.16
Cisco Firepower Threat Defense=6.2.3.17
Cisco Firepower Threat Defense=6.2.3.18
Cisco Firepower Threat Defense=6.4.0.10
Cisco Firepower Threat Defense=6.4.0.11
Cisco Firepower Threat Defense=6.4.0.12
Cisco Firepower Threat Defense=6.4.0.13
Cisco Firepower Threat Defense=6.4.0.14
Cisco Firepower Threat Defense=6.4.0.15
Cisco Firepower Threat Defense=6.4.0.16
Cisco Firepower Threat Defense=6.6.1
Cisco Firepower Threat Defense=6.6.3
Cisco Firepower Threat Defense=6.6.4
Cisco Firepower Threat Defense=6.6.5
Cisco Firepower Threat Defense=6.6.5.1
Cisco Firepower Threat Defense=6.6.5.2
Cisco Firepower Threat Defense=6.6.7
Cisco Firepower Threat Defense=6.6.7.1
Cisco Firepower Threat Defense=6.7.0
Cisco Firepower Threat Defense=6.7.0.1
Cisco Firepower Threat Defense=6.7.0.2
Cisco Firepower Threat Defense=6.7.0.3
Cisco Firepower Threat Defense=7.0.0
Cisco Firepower Threat Defense=7.0.0.1
Cisco Firepower Threat Defense=7.0.1
Cisco Firepower Threat Defense=7.0.1.1
Cisco Firepower Threat Defense=7.0.2
Cisco Firepower Threat Defense=7.0.2.1
Cisco Firepower Threat Defense=7.0.3
Cisco Firepower Threat Defense=7.0.4
Cisco Firepower Threat Defense=7.0.5
Cisco Firepower Threat Defense=7.1.0
Cisco Firepower Threat Defense=7.1.0.1
Cisco Firepower Threat Defense=7.1.0.2
Cisco Firepower Threat Defense=7.1.0.3
Cisco Firepower Threat Defense=7.2.0
Cisco Firepower Threat Defense=7.2.0.1
Cisco Firepower Threat Defense=7.2.1
Cisco Firepower Threat Defense=7.2.2
Cisco Firepower Threat Defense=7.2.3
Cisco Firepower Threat Defense=7.3.0
Cisco Firepower Threat Defense=7.3.1
Cisco Firepower Threat Defense=7.3.1.1

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2023-20256?

    CVE-2023-20256 has a high severity rating due to its potential to allow unauthorized access by bypassing access control lists.

  • How do I fix CVE-2023-20256?

    To remediate CVE-2023-20256, it is recommended to upgrade to a fixed version of Cisco Adaptive Security Appliance or Cisco Firepower Threat Defense software.

  • Which versions of Cisco software are affected by CVE-2023-20256?

    CVE-2023-20256 affects multiple versions of Cisco Adaptive Security Appliance and Cisco Firepower Threat Defense software, specifically within the specified version ranges.

  • What can an attacker exploit in CVE-2023-20256?

    An attacker can exploit CVE-2023-20256 to bypass configured access control lists and potentially gain unauthorized access to network traffic.

  • Has Cisco released a patch for CVE-2023-20256?

    Yes, Cisco has released patches to address CVE-2023-20256, and users should apply these updates promptly.

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