CVE-2021-40127

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

Description

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.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.30%
Vendor Advisory cisco.com
Affected: Cisco Cisco Small Business Smart and Managed Switches
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-40127?
CVE-2021-40127 has been scored as a medium severity vulnerability.
How to fix CVE-2021-40127?
To fix CVE-2021-40127, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-40127 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-40127 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-40127?
CVE-2021-40127 affects Cisco Cisco Small Business Smart and Managed Switches.
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