medium
4.3
CWE
120
Advisory Published
Updated

CVE-2021-34776: Cisco Small Business 220 Series Smart Switches Link Layer Discovery Protocol Vulnerabilities

First published: Wed Oct 06 2021(Updated: )

Multiple vulnerabilities exist in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business 220 Series Smart Switches. An unauthenticated, adjacent attacker could perform the following: Execute code on the affected device or cause it to reload unexpectedly Cause LLDP database corruption on the affected device For more information about these vulnerabilities, see the Details section of this advisory. Note: LLDP is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent). Cisco has released firmware updates that address these vulnerabilities.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco Business 220-8t-e-2g<=1.2.0.6
Cisco Business 220-8t-e-2g Firmware
Cisco Business 220-8p-e-2g<=1.2.0.6
Cisco Business 220-8p-e-2g Firmware
Cisco Business 220-8fp-e-2g Firmware<=1.2.0.6
Cisco Business 220-8fp-e-2g Firmware
Cisco Business 220-16T-2G Firmware<=1.2.0.6
Cisco Business 220-16t-2g Firmware
Cisco Business 220-16p-2g Firmware<=1.2.0.6
Cisco Business 220-16p-2g Firmware
Cisco Business 220-24t-4g Firmware<=1.2.0.6
Cisco Business 220-24t-4g Firmware
Cisco Business 220-24p-4g Firmware<=1.2.0.6
Cisco Business 220-24p-4g Firmware
Cisco Business 220-24fp-4g Firmware<=1.2.0.6
Cisco Business 220-24t-4g Firmware
Cisco Business 220-48T-4G Firmware<=1.2.0.6
Cisco Business 220-48t-4g Firmware
Cisco Business 220 Series Firmware<=1.2.0.6
Cisco Business 220-48p-4g
Cisco Business 220-24t-4x<=1.2.0.6
Cisco Business 220-24t-4x Firmware
Cisco Business 220-24p-4x<=1.2.0.6
Cisco Business 220-24p-4x Firmware
Cisco Business 220-24fp-4x Firmware<=1.2.0.6
Cisco Business 220-24fp-4x Firmware
Cisco Business 220 Series Firmware<=1.2.0.6
Cisco Business 220-48t-4x Firmware
Cisco Business 220-48p-4x Firmware<=1.2.0.6
Cisco Business 220-48p-4x Firmware
Cisco Business 220-48fp-4x Firmware<=1.2.0.6
Cisco Business 220-48fp-4x Firmware

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Reference Links

Frequently Asked Questions

  • What is CVE-2021-34776?

    CVE-2021-34776 is a vulnerability that exists in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business 220 Series Smart Switches.

  • What is the severity of CVE-2021-34776?

    The severity of CVE-2021-34776 is medium with a CVSS score of 4.3.

  • How can an attacker exploit CVE-2021-34776?

    An unauthenticated, adjacent attacker could execute code on the affected device or cause it to reload unexpectedly, and also cause LLDP database corruption.

  • Is Cisco Business 220-8t-e-2g vulnerable to CVE-2021-34776?

    The Cisco Business 220-8t-e-2g is vulnerable to CVE-2021-34776 if it is running firmware version 1.2.0.6 or earlier.

  • How can I fix CVE-2021-34776?

    To fix CVE-2021-34776, upgrade the firmware of the Cisco Small Business 220 Series Smart Switches to version 1.2.2.0 or later.

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