high
8.6
CWE
416
Advisory Published
Updated

CVE-2023-20027: Cisco IOS XE Software Virtual Fragmentation Reassembly Denial of Service Vulnerability

First published: Thu Mar 23 2023(Updated: )

A vulnerability in the implementation of the IPv4 Virtual Fragmentation Reassembly (VFR) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper reassembly of large packets that occurs when VFR is enabled on either a tunnel interface or on a physical interface that is configured with a maximum transmission unit (MTU) greater than 4,615 bytes. An attacker could exploit this vulnerability by sending fragmented packets through a VFR-enabled interface on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco IOS XE Web UI=3.9.0as
Cisco IOS XE Web UI=3.9.1s
Cisco IOS XE Web UI=3.9.2s
Cisco IOS XE Web UI=3.10.0s
Cisco IOS XE Web UI=3.10.1s
Cisco IOS XE Web UI=3.10.2as
Cisco IOS XE Web UI=3.10.2s
Cisco IOS XE Web UI=3.10.2ts
Cisco IOS XE Web UI=3.10.3s
Cisco IOS XE Web UI=3.10.4s
Cisco IOS XE Web UI=3.10.5s
Cisco IOS XE Web UI=3.10.6s
Cisco IOS XE Web UI=3.10.7s
Cisco IOS XE Web UI=3.10.8as
Cisco IOS XE Web UI=3.10.8s
Cisco IOS XE Web UI=3.10.9s
Cisco IOS XE Web UI=3.10.10s
Cisco IOS XE Web UI=3.11.0s
Cisco IOS XE Web UI=3.11.1s
Cisco IOS XE Web UI=3.11.2s
Cisco IOS XE Web UI=3.11.3s
Cisco IOS XE Web UI=3.11.4s
Cisco IOS XE Web UI=3.12.0s
Cisco IOS XE Web UI=3.12.1s
Cisco IOS XE Web UI=3.12.2s
Cisco IOS XE Web UI=3.12.3s
Cisco IOS XE Web UI=3.12.4s
Cisco IOS XE Web UI=3.13.0s
Cisco IOS XE Web UI=3.13.1s
Cisco IOS XE Web UI=3.13.2s
Cisco IOS XE Web UI=3.13.3s
Cisco IOS XE Web UI=3.13.4s
Cisco IOS XE Web UI=3.13.5s
Cisco IOS XE Web UI=3.13.6as
Cisco IOS XE Web UI=3.13.6s
Cisco IOS XE Web UI=3.13.7s
Cisco IOS XE Web UI=3.13.8s
Cisco IOS XE Web UI=3.13.9s
Cisco IOS XE Web UI=3.13.10s
Cisco IOS XE Web UI=3.14.0s
Cisco IOS XE Web UI=3.14.1s
Cisco IOS XE Web UI=3.14.2s
Cisco IOS XE Web UI=3.14.3s
Cisco IOS XE Web UI=3.14.4s
Cisco IOS XE Web UI=3.15.0s
Cisco IOS XE Web UI=3.15.1cs
Cisco IOS XE Web UI=3.15.1s
Cisco IOS XE Web UI=3.15.2s
Cisco IOS XE Web UI=3.15.3s
Cisco IOS XE Web UI=3.15.4s
Cisco IOS XE Web UI=3.16.0cs
Cisco IOS XE Web UI=3.16.0s
Cisco IOS XE Web UI=3.16.1as
Cisco IOS XE Web UI=3.16.2s
Cisco IOS XE Web UI=3.16.3s
Cisco IOS XE Web UI=3.16.4as
Cisco IOS XE Web UI=3.16.4bs
Cisco IOS XE Web UI=3.16.4cs
Cisco IOS XE Web UI=3.16.4ds
Cisco IOS XE Web UI=3.16.4es
Cisco IOS XE Web UI=3.16.4gs
Cisco IOS XE Web UI=3.16.5as
Cisco IOS XE Web UI=3.16.5bs
Cisco IOS XE Web UI=3.16.5s
Cisco IOS XE Web UI=3.16.6bs
Cisco IOS XE Web UI=3.16.6s
Cisco IOS XE Web UI=3.16.7as
Cisco IOS XE Web UI=3.16.7bs
Cisco IOS XE Web UI=3.16.7s
Cisco IOS XE Web UI=3.16.8s
Cisco IOS XE Web UI=3.16.9s
Cisco IOS XE Web UI=3.16.10s
Cisco IOS XE Web UI=3.17.0s
Cisco IOS XE Web UI=3.17.1s
Cisco IOS XE Web UI=3.17.2s
Cisco IOS XE Web UI=3.17.3s
Cisco IOS XE Web UI=3.17.4s
Cisco IOS XE Web UI=3.18.0as
Cisco IOS XE Web UI=3.18.2asp
Cisco IOS XE Web UI=16.2.1
Cisco IOS XE Web UI=16.2.2
Cisco IOS XE Web UI=16.3.1
Cisco IOS XE Web UI=16.3.1a
Cisco IOS XE Web UI=16.3.2
Cisco IOS XE Web UI=16.3.3
Cisco IOS XE Web UI=16.3.4
Cisco IOS XE Web UI=16.3.5
Cisco IOS XE Web UI=16.3.6
Cisco IOS XE Web UI=16.3.7
Cisco IOS XE Web UI=16.3.8
Cisco IOS XE Web UI=16.3.9
Cisco IOS XE Web UI=16.3.10
Cisco IOS XE Web UI=16.3.11
Cisco IOS XE Web UI=16.4.1
Cisco IOS XE Web UI=16.4.2
Cisco IOS XE Web UI=16.4.3
Cisco IOS XE Web UI=16.5.1
Cisco IOS XE Web UI=16.5.1b
Cisco IOS XE Web UI=16.5.2
Cisco IOS XE Web UI=16.5.3
Cisco IOS XE Web UI=16.6.1
Cisco IOS XE Web UI=16.6.2
Cisco IOS XE Web UI=16.6.3
Cisco IOS XE Web UI=16.6.4
Cisco IOS XE Web UI=16.6.4s
Cisco IOS XE Web UI=16.6.5
Cisco IOS XE Web UI=16.6.6
Cisco IOS XE Web UI=16.6.7
Cisco IOS XE Web UI=16.6.8
Cisco IOS XE Web UI=16.6.9
Cisco IOS XE Web UI=16.6.10
Cisco IOS XE Web UI=16.7.1
Cisco IOS XE Web UI=16.7.2
Cisco IOS XE Web UI=16.7.3
Cisco IOS XE Web UI=16.8.1
Cisco IOS XE Web UI=16.8.1s
Cisco IOS XE Web UI=16.8.2
Cisco IOS XE Web UI=16.8.3
Cisco IOS XE Web UI=16.9.1
Cisco IOS XE Web UI=16.9.1s
Cisco IOS XE Web UI=16.9.2
Cisco IOS XE Web UI=16.9.2s
Cisco IOS XE Web UI=16.9.3
Cisco IOS XE Web UI=16.9.3s
Cisco IOS XE Web UI=16.9.4
Cisco IOS XE Web UI=16.9.5
Cisco IOS XE Web UI=16.9.6
Cisco IOS XE Web UI=16.9.7
Cisco IOS XE Web UI=16.9.8
Cisco IOS XE Web UI=16.9.8a
Cisco IOS XE Web UI=16.9.8c
Cisco IOS XE Web UI=16.10.1
Cisco IOS XE Web UI=16.10.1a
Cisco IOS XE Web UI=16.10.1b
Cisco IOS XE Web UI=16.10.1e
Cisco IOS XE Web UI=16.10.1s
Cisco IOS XE Web UI=16.10.2
Cisco IOS XE Web UI=16.10.3
Cisco IOS XE Web UI=16.11.1
Cisco IOS XE Web UI=16.11.1a
Cisco IOS XE Web UI=16.11.1c
Cisco IOS XE Web UI=16.11.1s
Cisco IOS XE Web UI=16.11.2
Cisco IOS XE Web UI=16.12.1
Cisco IOS XE Web UI=16.12.1a
Cisco IOS XE Web UI=16.12.1c
Cisco IOS XE Web UI=16.12.1s
Cisco IOS XE Web UI=16.12.2
Cisco IOS XE Web UI=16.12.2s
Cisco IOS XE Web UI=16.12.2t
Cisco IOS XE Web UI=16.12.3
Cisco IOS XE Web UI=16.12.3s
Cisco IOS XE Web UI=16.12.4
Cisco IOS XE Web UI=16.12.5
Cisco IOS XE Web UI=16.12.6
Cisco IOS XE Web UI=16.12.7
Cisco IOS XE Web UI=16.12.8
Cisco IOS XE Web UI=17.1.1
Cisco IOS XE Web UI=17.1.1s
Cisco IOS XE Web UI=17.1.1t
Cisco IOS XE Web UI=17.1.2
Cisco IOS XE Web UI=17.1.3
Cisco IOS XE Web UI=17.2.1
Cisco IOS XE Web UI=17.2.1r
Cisco IOS XE Web UI=17.2.1v
Cisco IOS XE Web UI=17.2.2
Cisco IOS XE Web UI=17.2.3
Cisco IOS XE Web UI=17.3.1
Cisco IOS XE Web UI=17.3.1a
Cisco IOS XE Web UI=17.3.2
Cisco IOS XE Web UI=17.3.3
Cisco IOS XE Web UI=17.3.4
Cisco IOS XE Web UI=17.3.4a
Cisco IOS XE Web UI=17.3.5
Cisco IOS XE Web UI=17.4.1
Cisco IOS XE Web UI=17.4.1a
Cisco IOS XE Web UI=17.4.1b
Cisco IOS XE Web UI=17.4.2
Cisco IOS XE Web UI=17.5.1
Cisco IOS XE Web UI=17.5.1a
Cisco IOS XE Web UI=17.6.1
Cisco IOS XE Web UI=17.6.1a
Cisco IOS XE Web UI=17.6.2
Cisco IOS XE Web UI=17.6.3
Cisco IOS XE Web UI=17.6.3a
Cisco IOS XE Web UI=17.7.1
Cisco IOS XE Web UI=17.7.1a
Cisco IOS XE Web UI=17.7.2
Cisco IOS XE Web UI=17.8.1
Cisco IOS XE Web UI=17.8.1a
Cisco Catalyst 8000V Edge
Cisco Cloud Services Router 1000V
Cisco 1000 Integrated Services Router
Cisco 1100-4g/6g Integrated Services Router
Cisco 1100-4g/6g Integrated Services Router
Cisco 1109-4p Integrated Services Router
Cisco 1100 Integrated Services Router
Cisco 1100 Integrated Services Router
Cisco 1100 Series Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1111x-8p
Cisco 111x Integrated Services Router
Cisco 111x Integrated Services Router
Cisco 1120 Integrated Services Router
Cisco 1131 Integrated Services Router
Cisco 1160 Integrated Services Router
Cisco 4221 Integrated Services Router
Cisco 4321/k9 Integrated Services Router
Cisco 4331/k9-rf Integrated Services Router
Cisco 4351/k9-rf Integrated Services Router
Cisco 4431 Integrated Services Router
Cisco 4451-X Integrated Services Router
Cisco 4441 Integrated Services Router
Cisco c8200l-1n-4t
Cisco c8200l-1n-4t
Cisco Catalyst 8500L Series Router
Cisco Catalyst 8300-1N1S-4T2X
Cisco Catalyst 8300
Cisco Catalyst 8300-2N2S-4T2X
Cisco Catalyst 8300

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2023-20027?

    CVE-2023-20027 has a severity rating that can cause a denial of service (DoS) condition on an affected device.

  • How do I fix CVE-2023-20027?

    To fix CVE-2023-20027, you should update Cisco IOS XE Software to the latest version that has addressed the vulnerability.

  • What devices are affected by CVE-2023-20027?

    CVE-2023-20027 affects multiple versions of Cisco IOS XE Software, specifically from version 3.9.0as to 17.8.1.

  • Can CVE-2023-20027 be exploited remotely?

    Yes, CVE-2023-20027 can be exploited by unauthenticated, remote attackers.

  • What impact does CVE-2023-20027 have on network services?

    CVE-2023-20027 can cause denial of service, impacting the availability of network services on affected devices.

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