CVE-2026-20010
highpriority · track · 0EPSS 0.002 · 8 %ileDEEUUSEPSS · scored 2026-10-27
A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the LLDP process to restart, which could cause an affected device to reload unexpectedly. This vulnerability is due to improper handling of specific fields in an LLDP frame. An attacker could exploit this vulnerability by sending a crafted LLDP packet to an interface of an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Note: LLDP is a Layer 2 link protocol. To exploit this vulnerability, an attacker would need to be directly connected to an interface of an affected device, either physically or logically (for example, through a Layer 2 Tunnel configured to transport the LLDP protocol).
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed4.3(4b)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(4c)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(4d)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(4e)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(4f)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(5a)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(5c)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(5d)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(5e)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(6a)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(6b)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(6c)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed4.3(6d)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(1) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(1) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(2) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(2) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3o) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3p) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3q) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3r) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3w) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(3x) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(4) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(4) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(4a) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(4a) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(4g) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(4h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(99w) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.3(99x) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.4(1) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.4(1) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.4(2) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 10.4(2) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(2h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(2j) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(3d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(3e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(3g) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(4c) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(5h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(5j) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(6c) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(6h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(7e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(8e) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(8f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(8h) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(9c) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.0(9d) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.1(1f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.1(2f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.1(2g) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.1(3f) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS System Software in ACI Mode 16.1(3g) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–7.4
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (110)
Products and version ranges known to be affected.
- Cisco NX-OS Link Layer Discovery Protocolall versionscert_bundDEcpe:/o:cisco:nx-os:link_layer_discovery_protocol
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-0521Cisco NX-OS Software Link Layer Discovery Protocol: Schwachstelle ermöglicht Denial of ServiceDeutsch2026-02-25csaf · cert_bundDE
Ein Angreifer aus einem angrenzenden Netzwerk kann eine Schwachstelle in Cisco NX-OS ausnutzen, um einen Denial of Service Angriff durchzuführen.
- cisco-sa-n3kn9k_aci_lldp_dos-NdgRrrA3Cisco NX-OS Software Link Layer Discovery Protocol Denial of Service Vulnerability2026-02-25csaf · cisco_csafUS
A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the LLDP process to restart, which could cause an affected device to reload unexpectedly. This vulnerability is due to improper handling of specific fields in an LLDP frame. An attacker could exploit this vulnerability by sending a crafted LLDP packet to an interface of an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Note: LLDP is a Layer 2 link protocol. To exploit this vulnerability, an attacker would need to be directly connected to an interface of an affected device, either physically or logically (for example, through a Layer 2 Tunnel configured to transport the LLDP protocol). Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the February 2026 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: February 2026 Semiannual Cisco FXOS and NX-OS Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75740"].
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (3)
External citations — patches, advisories, analysis.
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n3kn9k_aci_lldp_dos-NdgRrrA3cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n3kn9k_aci_lldp_dos-NdgRrrA3enisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n3kn9k_aci_lldp_dos-NdgRrrA3nvd
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