Denial of service in Cisco Small Business 200, 300, and 500 Series Switches

1) Input validation error

EUVDB-ID: #VU57957

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40127

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input in the web-based management interface. A remote attacker can send a crafted HTTP request and perform a denial of service (DoS) attack.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Cisco Small Business 200 Series Smart Switches: All versions

Cisco Small Business 300 Series Managed Switches: All versions

Cisco Small Business 500 Series Stackable Managed Switches: All versions

CPE2.3

• cpe:2.3:h:cisco_systems:cisco_small_business_200_series_smart_switches:*:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:cisco_small_business_300_series_managed_switches:*:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:cisco_small_business_500_series_stackable_managed_switches:*:*:*:*:*:*:*:*

External links

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-smb-switches-web-dos-xMyFFkt8

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.