Cisco Security Advisory
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CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
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Multiple vulnerabilities in the Operation, Administration, and Maintenance (OAM) feature of Cisco NX-OS Software, known as Next Generation OAM (NGOAM), could allow an unauthenticated, remote attacker to execute arbitrary code with root privileges or cause a denial of service (DoS) condition on an affected device.
These vulnerabilities are due to improper input validation of IP traffic when NGOAM is enabled. An attacker could exploit these vulnerabilities by sending crafted packets to an IP interface on an affected device. A successful exploit could allow the attacker to execute arbitrary code with root privileges and could cause process crashes, which could result in a reload of the device and a DoS condition.
Note: Feature requirements vary for each vulnerability. For details, see the Vulnerable Products section of this advisory.
Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.
This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ngoam-rce-LWKQ4BUThis advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of October 7, 2026, Security Advisories. For further documentation of improvements and fixes in Cisco NX-OS Software, see Cisco NX-OS Software Security Hardening Release: October 2026.
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Vulnerable Products
These vulnerabilities affect Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode if NGOAM is enabled and specific features are configured, as detailed in the following list:
- CVE-2026-76485: To be affected by this vulnerability, the switch must have NGOAM enabled. That is the only requirement.
- CVE-2026-76486: To be affected by this vulnerability, the switch must have NGOAM enabled and either Segment Routing over IPv6 (SRv6) or Network Virtualization (NV) Overlay enabled. NV Overlay also requires a VXLAN Ethernet VPN (EVPN) VXLAN Network Identifier (VNI) mapped to a Network Virtualization Endpoint (NVE) interface with at least one peer VXLAN Tunnel Endpoint (VTEP) learned (for example, BGP EVPN or an ingress-replication static peer).
- CVE-2026-76501: To be affected by this vulnerability, the switch must have both NGOAM and SRv6 enabled.
Note: Cisco Nexus 3000 Series switches do not support SRv6, and only a subset of Cisco Nexus 9000 Series switches support SRv6. For more information, see Cisco Nexus 9000 Series NX-OS SRv6 Configuration Guide, Release 10.6(x).
Determine the Status of NGOAM
To determine whether a device is configured with NGOAM enabled, use the show feature | include ngoam command at the Cisco NX-OS CLI. The following example shows NGOAM enabled on a device that is running Cisco NX-OS Software:
switch# show feature | include ngoam
ngoam 1 enabledDetermine the Status of NV Overlay
To determine whether a device is configured with NV Overlay enabled, use the show feature | include nve command at the Cisco NX-OS CLI. The following example shows NV Overlay enabled on a device that is running Cisco NX-OS Software:
switch# show feature | include nve
nve 1 disabled
switch# configure
switch(config)# feature nv overlay
switch(config)# show feature | include nve
nve 1 enabledDetermine the Status of the NV Overlay VXLAN EVPN VNI
To determine whether a device is configured with VXLAN EVPN VNI mapped on an NVE interface with at least one peer VTEP learned, use the following commands at the Cisco NX-OS CLI:
- show running-config | begin "interface nve"
- show nve vni
- show nve peers
If all three commands return data, as shown in the following example, then the device may be affected by CVE-2026-76486.
switch# show running-config | begin "interface nve"
interface nve1
source-interface loopback1
member vni 160010 mcast-group 203.0.113.1
member vni 160020 mcast-group 203.0.113.1
no shutdown
switch# show nve vni
Interface VNI Multicast-group VNI State
--------- -------- --------------- ---------
nve1 160010 203.0.113.1 Up
switch# show nve peers
Interface Peer-IP Peer-State
--------- ------------ ----------
nve1 192.168.2.1 UpDetermine the Status of SRv6
To determine whether a device is configured with SRv6 enabled, use the show feature | include srv6 command at the Cisco NX-OS CLI. The following example shows SRv6 enabled on a device that is running Cisco NX-OS Software:
switch# show feature | include srv6
srv6 1 enabledProducts Confirmed Not Vulnerable
Only products listed in the Vulnerable Products section of this advisory are known to be affected by this vulnerability.
Cisco has confirmed that this vulnerability does not affect the following Cisco products:
- Firepower 1000 Series
- Firepower 2100 Series
- Firepower 4100 Series
- Firepower 9300 Security Appliances
- MDS 9000 Series Multilayer Switches
- Nexus 7000 Series Switches
- Nexus 9000 Series Fabric Switches in ACI mode
- Secure Firewall 200 Series
- Secure Firewall 1200 Series
- Secure Firewall 3100 Series
- Secure Firewall 4200 Series
- Secure Firewall 6100 Series
- UCS 6300 Series Fabric Interconnects
- UCS 6400 Series Fabric Interconnects
- UCS 6500 Series Fabric Interconnects
- UCS 6600 Series Fabric Interconnects
- UCS X-Series Direct Fabric Interconnect 9108 100G
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The VXLAN NGOAM feature on Cisco Nexus 9000 Series Switches provides loop detection and mitigation capabilities, particularly for Layer 3 interfaces and VXLAN OAM functionalities. For more information, see Cisco Nexus 9000 Series NX-OS VXLAN Configuration Guide, Release 10.4(x).
The SRv6 NGOAM feature on Cisco Nexus 9000 Series Switches provides monitoring and diagnostic capabilities for SRv6 paths. It assists with fault detection and troubleshooting by using IPv6 ping and pathtrace mechanisms to verify path connectivity and isolate forwarding problems in the network. For more information, see Cisco Nexus 9000 Series NX-OS SRv6 Configuration Guide, Release 10.6(x).
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There are no workarounds that address these vulnerabilities.
If the NGOAM feature is not required, disabling it removes the attack vector and is a mitigation for all three vulnerabilities. Disable the NGOAM by using the Cisco NX-OS CLI command no feature ngoam in global configuration mode on a Cisco Nexus 3000 Series or 9000 Series Switch.
While this mitigation has been deployed and was proven successful in a test environment, customers should determine the applicability and effectiveness in their own environment and under their own use conditions. Customers should be aware that any workaround or mitigation that is implemented may negatively impact the functionality or performance of their network based on intrinsic customer deployment scenarios and limitations. Customers should not deploy any workarounds or mitigations before first evaluating the applicability to their own environment and any impact to such environment.
Live Protect Shields
Cisco has released Live Protect shields for CVE-2026-76485, CVE-2026-76486, and CVE-2026-76501 to temporarily mitigate these vulnerabilities for Cisco NX-OS Software.
For information about Live Protect for Cisco NX-OS Software, see Cisco Nexus 9000 Series NX-OS Security Configuration Guide.
Note: Live Protect shields are temporary mitigations to bridge the gap until software updates can be scheduled. To remediate this vulnerability, upgrade to a fixed software release as noted in the Fixed Software section of this advisory.
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Cisco considers any workarounds and mitigations (if applicable) to be temporary solutions until an upgrade to a fixed software release is available. To remediate these vulnerabilities and avoid future exposure as described in this advisory, Cisco strongly recommends that customers upgrade to the fixed software indicated in this advisory.
Cisco NX-OS Software
To help customers determine their exposure to vulnerabilities in Cisco NX-OS Software, Cisco provides the Cisco Software Checker. This tool identifies any Cisco security advisories that impact a specific software release and the earliest release that fixes the vulnerabilities that are described in each advisory (“First Fixed”). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities described in all the advisories that the Software Checker identifies (“Combined First Fixed”).
To use the tool, go to the Cisco Software Checker page and follow the instructions. Alternatively, use the following form to search for vulnerabilities that affect a specific software release. To use the form, follow these steps:
- Choose which advisories the tool will search—only this advisory, only advisories with a Critical or High Security Impact Rating (SIR), or all advisories.
- Choose the appropriate software.
- Choose the appropriate platform.
- Enter a release number—for example, 10.4(4) for Cisco Nexus 3000 Series Switches or 16.0(8e) for Cisco NX-OS Software in ACI mode.
- Click Check.
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The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
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These vulnerabilities were found during internal security testing.
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To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
For additional information on Cisco's vulnerability management, disclosure cadence, and software patching strategy, see Cisco's Transition to a Risk-Based Vulnerability Disclosure Model.
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Show LessVersion Description Section Status Date 1.0 Initial public release. — Final 2026-OCT-07
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SOFTWARE DOWNLOADS AND TECHNICAL SUPPORT
The Cisco Support and Downloads page on Cisco.com provides information about licensing and downloads. This page can also display customer device support coverage for customers who use the My Devices tool. Please note that customers may download only software that was procured from Cisco directly or through a Cisco authorized reseller or partner and for which the license is still valid.
Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco Technical Assistance Center (TAC). Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.
When considering software upgrades, customers are advised to regularly consult the advisories for the relevant Cisco products to determine exposure and a complete upgrade solution. In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
LEGAL DISCLAIMER DETAILS
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Copies or summaries of the information contained in this Security Advisory may lack important information or contain factual errors. Customers are advised to visit the Cisco Security Advisories page for the most recent version of this Security Advisory. The Cisco Product Security Incident Response Team (PSIRT) assesses only the affected and fixed release information that is documented in this advisory. See the Cisco Security Vulnerability Policy for more information.