#VU56875 Input validation error in Cisco Systems, Inc products - CVE-2021-34714

Vulnerability identifier: #VU56875

Vulnerability risk: Medium

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

CVE-ID: CVE-2021-34714

CWE-ID: CWE-20

Exploitation vector: Adjecent network

Exploit availability: No public exploit available

Vulnerable software:
Cisco FXOS
Cisco IOS
Cisco IOS XE
Cisco IOS XR
Cisco NX-OS
Cisco UCS
Cisco Firepower 4100 Series Next-Generation Firewall
Cisco Firepower 9300 Security Appliance
Cisco MDS 9000 Series Multilayer Switches
Cisco Nexus 3000 Series Switches
Nexus 5500 Platform Switches
Nexus 5600 Platform Switches
Cisco Nexus 6000 Series Switches
Cisco Nexus 7000 Series Switches
Cisco Nexus 9000 Series Switches NX-OS Mode
UCS 6200 Series Fabric Interconnects
UCS 6300 Series Fabric Interconnects
UCS 6400 Series Fabric Interconnects

Software vendor:
Cisco Systems, Inc

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 Unidirectional Link Detection (UDLD) feature. A remote attacker on the local network can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Install updates from vendor's website.

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ