#VU49026 Integer overflow in Cisco Systems, Inc products - CVE-2020-3120

Vulnerability identifier: #VU49026

Vulnerability risk: Low

CVSSv4.0: 4.9 [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:Clear]

CVE-ID: CVE-2020-3120

CWE-ID: CWE-190

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Cisco FXOS
Operating systems & Components / Operating system
Cisco IOS XR
Operating systems & Components / Operating system
Cisco NX-OS
Operating systems & Components / Operating system
Cisco MDS 9000 Series Multilayer Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco IOS XRv 9000 Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9000 Series Aggregation Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Network Convergence System 6000 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Network Convergence System 5500 Series
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Network Convergence System 5000 Series
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Network Convergence System 560 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Network Convergence System 540 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 9000 Series Switches NX-OS Mode
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 9000 Series Switches in ACI Mode
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 7000 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 6000 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Nexus 5600 Platform Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Nexus 5500 Platform Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Nexus 3000 Series Switches
Hardware solutions / Routers & switches, VoIP, GSM, etc
Nexus 1000V Switch for VMware vSphere
Hardware solutions / Routers & switches, VoIP, GSM, etc
Nexus 1000V Switch for Microsoft Hyper-V
Hardware solutions / Routers & switches, VoIP, GSM, etc
UCS 6400 Series Fabric Interconnects
Hardware solutions / Routers & switches, VoIP, GSM, etc
UCS 6300 Series Fabric Interconnects
Hardware solutions / Routers & switches, VoIP, GSM, etc
UCS 6200 Series Fabric Interconnects
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Firepower 9300 Security Appliance
Hardware solutions / Security hardware applicances
Cisco Firepower 4100 Series Next-Generation Firewall
Hardware solutions / Firmware
Cisco Carrier Routing System
Hardware solutions / Firmware
Cisco Network Convergence System 1000 Series
Hardware solutions / Firmware
Nexus 1000 Virtual Edge for VMware vSphere
Server applications / Other server solutions

Vendor: Cisco Systems, Inc

Description

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

The vulnerability exists due to integer overflow in the Cisco Discovery Protocol implementation. A remote attacker on the local network can send a specially crafted Cisco Discovery Protocol packet, trigger integer overflow and cause a denial of service condition on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco FXOS: 2.2 - 2.7

Cisco IOS XR: 5.2.5, 6.4.2, 6.5.3, 6.6 - 6.6.25, 7.0 - 7.0.1

Cisco NX-OS: 5.2 - 14.2

Cisco MDS 9000 Series Multilayer Switches: 6.2.1 - 8.4.2.9

Cisco IOS XRv 9000 Router: All versions

Cisco Firepower 9300 Security Appliance: 2.4.200.10

Cisco Firepower 4100 Series Next-Generation Firewall: All versions

Cisco Carrier Routing System: All versions

Cisco ASR 9000 Series Aggregation Services Routers: 6.1.3

Cisco Network Convergence System 6000 Series Routers: All versions

Network Convergence System 5500 Series: All versions

Cisco Network Convergence System 5000 Series: All versions

Cisco Network Convergence System 1000 Series: All versions

Cisco Network Convergence System 560 Series Routers: All versions

Cisco Network Convergence System 540 Series Routers: All versions

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

Cisco Nexus 9000 Series Switches in ACI Mode: All versions

Cisco Nexus 7000 Series Switches: All versions

Cisco Nexus 6000 Series Switches: All versions

Nexus 5600 Platform Switches: All versions

Nexus 5500 Platform Switches: All versions

Cisco Nexus 3000 Series Switches: All versions

Nexus 1000V Switch for VMware vSphere: 5.2.1 SV5.1.2

Nexus 1000V Switch for Microsoft Hyper-V: All versions

Nexus 1000 Virtual Edge for VMware vSphere: All versions

UCS 6400 Series Fabric Interconnects: 3.2 - 4.0

UCS 6300 Series Fabric Interconnects: 3.2 - 4.0

UCS 6200 Series Fabric Interconnects: 3.2 - 4.0

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External links
https://packetstormsecurity.com/files/156203/Cisco-Discovery-Protocol-CDP-Remote-Device-Takeover.html
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-fxnxos-iosxr-cdp-dos

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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 local network (LAN).

Is there known malware, which exploits this vulnerability?

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