Vulnerability identifier: #VU46104

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-3517

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco FXOS
Operating systems & Components / Operating system
Cisco NX-OS
Operating systems & Components / Operating system
Cisco Firepower 4100 Series Next-Generation Firewall
Hardware solutions / Firmware
Cisco Firepower 9300 Security Appliance
Hardware solutions / Security hardware applicances
Cisco MDS 9000 Series Multilayer Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 3000 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 5500 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 5600 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 6000 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 7000 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 9000 Series Switches NX-OS Mode
Hardware solutions / Routers & switches, VoIP, GSM, etc
UCS 6200 Series Fabric Interconnects
Hardware solutions / Routers & switches, VoIP, GSM, etc
UCS 6300 Series Fabric Interconnects
Hardware solutions / Routers & switches, VoIP, GSM, etc
UCS 6400 Series Fabric Interconnects
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

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

The vulnerability exists due to a NULL pointer dereference error in the Cisco Fabric Services component . A remote attacker can send malicious Cisco Fabric Services messages and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco FXOS: 1.1 - 2.2

Cisco NX-OS: All versions

Cisco Firepower 4100 Series Next-Generation Firewall: 2.7.1.122

Cisco Firepower 9300 Security Appliance: 2.7.1.122

Cisco MDS 9000 Series Multilayer Switches: 8.4.1

Cisco Nexus 3000 Series Switches: All versions

Cisco Nexus 5500 Series Switches: 7.3.7 N1.0.786

Cisco Nexus 5600 Series Switches: 7.3.7 N1.0.786

Cisco Nexus 6000 Series Switches: 7.3.7 N1.0.786

Cisco Nexus 7000 Series Switches: 8.4.1

Cisco Nexus 9000 Series Switches NX-OS Mode: All versions

UCS 6200 Series Fabric Interconnects: 4.1.1

UCS 6300 Series Fabric Interconnects: 4.1.1

UCS 6400 Series Fabric Interconnects: 4.1.1

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fxos-nxos-cfs-dos-dAmnymbd

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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