medium
4.3
CWE
120
Advisory Published
Updated

CVE-2021-34777: 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-2021-34777?

    CVE-2021-34777 is a vulnerability in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business 220 Series Smart Switches.

  • What is the severity of CVE-2021-34777?

    The severity of CVE-2021-34777 is medium with a CVSS score of 4.3.

  • What is the affected software for CVE-2021-34777?

    The affected software for CVE-2021-34777 includes Cisco Business 220 Series Smart Switches with firmware version up to and including 1.2.0.6.

  • What can an attacker do with CVE-2021-34777?

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

  • How can I fix CVE-2021-34777?

    To fix CVE-2021-34777, it is recommended to upgrade your Cisco Business 220 Series Smart Switches to a firmware version beyond 1.2.0.6.

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