CVE-2021-40127: Cisco Small Business 200, 300, and 500 Series Switches Web-Based Management Interface Denial of Service Vulnerability

Published Nov 4, 2021
·
Updated

A vulnerability in the web-based management interface of Cisco Small Business 200 Series Smart Switches, Cisco Small Business 300 Series Managed Switches, and Cisco Small Business 500 Series Stackable Managed Switches could allow an unauthenticated, remote attacker to render the web-based management interface unusable, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to cause a permanent invalid redirect for requests sent to the web-based management interface of the device, resulting in a DoS condition.

Affected Software

132 affected components
Cisco Sf200-24 Firmware
Cisco Sf200-24
Cisco Sf200-24fp Firmware
Cisco Sf200-24fp
Cisco Sf200-24p Firmware
Cisco Sf200-24p
Cisco Sf200-48 Firmware
Cisco Sf200-48
Cisco Sf200-48p Firmware
Cisco Sf200-48p
Cisco Sf200e-24 Firmware
Cisco Sf200e-24
Cisco Sf200e-24p Firmware
Cisco Sf200e-24p
Cisco Sf200e-48 Firmware
Cisco Sf200e-48
Cisco Sf200e-48p Firmware
Cisco Sf200e-48p
Cisco Sg200-08 Firmware
Cisco Sg200-08
Cisco Sg200-08p Firmware
Cisco Sg200-08p
Cisco Sg200-10fp Firmware
Cisco Sg200-10fp
Cisco Sg200-18 Firmware
Cisco Sg200-18
Cisco Sg200-26 Firmware
Cisco Sg200-26
Cisco Sg200-26fp Firmware
Cisco Sg200-26fp
Cisco Sg200-26p Firmware
Cisco Sg200-26p
Cisco Sg200-50 Firmware
Cisco Sg200-50
Cisco Sg200-50fp Firmware
Cisco Sg200-50fp
Cisco Sg200-50p Firmware
Cisco Sg200-50p
Cisco Sf300-08 Firmware=1.4.11.02
Cisco Sf300-08
Cisco Sf300-24 Firmware=1.4.11.02
Cisco Sf300-24
Cisco Sf300-24mp Firmware=1.4.11.02
Cisco Sf300-24mp
Cisco Sf300-24p Firmware=1.4.11.02
Cisco Sf300-24p
Cisco Sf300-24pp Firmware=1.4.11.02
Cisco Sf300-24pp
Cisco Sf300-48 Firmware=1.4.11.02
Cisco Sf300-48
Cisco Sf300-48p Firmware=1.4.11.02
Cisco Sf300-48p
Cisco Sf300-48pp Firmware=1.4.11.02
Cisco Sf300-48pp
Cisco Sf302-08 Firmware=1.4.11.02
Cisco Sf302-08
Cisco Sf302-08mp Firmware=1.4.11.02
Cisco Sf302-08mp
Cisco Sf302-08mpp Firmware=1.4.11.02
Cisco Sf302-08mpp
Cisco Sf302-08p Firmware=1.4.11.02
Cisco Sf302-08p
Cisco Sf302-08pp Firmware=1.4.11.02
Cisco Sf302-08pp
Cisco Sg300-10 Firmware=1.4.11.02
Cisco Sg300-10
Cisco Sg300-10mp Firmware=1.4.11.02
Cisco Sg300-10mp
Cisco Sg300-10mpp Firmware=1.4.11.02
Cisco Sg300-10mpp
Cisco Sg300-10p Firmware=1.4.11.02
Cisco Sg300-10p
Cisco Sg300-10pp Firmware=1.4.11.02
Cisco Sg300-10pp
Cisco Sg300-sfp Firmware=1.4.11.02
Cisco Sg300-sfp
Cisco Sg300-20 Firmware=1.4.11.02
Cisco Sg300-20
Cisco Sg300-28 Firmware=1.4.11.02
Cisco Sg300-28
Cisco Sg300-28mp Firmware=1.4.11.02
Cisco Sg300-28mp
Cisco Sg300-28p Firmware=1.4.11.02
Cisco Sg300-28p
Cisco Sg300-28pp Firmware=1.4.11.02
Cisco Sg300-28pp
Cisco Sg300-28sfp Firmware=1.4.11.02
Cisco Sg300-28sfp
Cisco Sg300-52 Firmware=1.4.11.02
Cisco Sg300-52
Cisco Sg300-52mp Firmware=1.4.11.02
Cisco Sg300-52mp
Cisco Sg300-52p Firmware=1.4.11.02
Cisco Sg300-52p
Cisco Sf500-24 Firmware
Cisco Sf500-24
Cisco Sf500-24mp Firmware
Cisco Sf500-24mp
Cisco Sf500-24p Firmware
Cisco Sf500-24p
Cisco Sf500-48 Firmware
Cisco Sf500-48
Cisco Sf500-48mp Firmware
Cisco Sf500-48mp
Cisco Sf500-48p Firmware
Cisco Sf500-48p
Cisco Sg500-28 Firmware
Cisco Sg500-28
Cisco Sg500-28mpp Firmware
Cisco Sg500-28mpp
Cisco Sg500-28p Firmware
Cisco Sg500-28p
Cisco Sg500-52 Firmware
Cisco Sg500-52
Cisco Sg500-52mp Firmware
Cisco Sg500-52mp
Cisco Sg500-52p Firmware
Cisco Sg500-52p
Cisco Sg500x-24 Firmware
Cisco Sg500x-24
Cisco Sg500x-24mpp Firmware
Cisco Sg500x-24mpp
Cisco Sg500x-24p Firmware
Cisco Sg500x-24p
Cisco Sg500x-48 Firmware
Cisco Sg500x-48
Cisco Sg500x-48mpp Firmware
Cisco Sg500x-48mpp
Cisco Sg500x-48p Firmware
Cisco Sg500x-48p
Cisco Sg500xg-8f8t Firmware
Cisco Sg500xg-8f8t

Event History

Nov 4, 2021
CVE Published
via MITRE·03:30 PM
Data Sourced
via MITRE·03:30 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2021-40127?

The severity of CVE-2021-40127 is rated as medium, allowing unauthenticated remote attackers to exploit the vulnerability.

2

How do I fix CVE-2021-40127?

To fix CVE-2021-40127, it is recommended to apply the latest firmware updates provided by Cisco for affected devices.

3

Which Cisco devices are affected by CVE-2021-40127?

CVE-2021-40127 affects Cisco Small Business 200, 300, and 500 Series switches.

4

What type of attack does CVE-2021-40127 allow?

CVE-2021-40127 allows an unauthenticated remote attacker to launch a denial of service attack via the web-based management interface.

5

Are all versions of affected Cisco switches vulnerable to CVE-2021-40127?

Not all versions of affected Cisco switches are vulnerable; it primarily affects those running specific firmware versions.

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