Description
A vulnerability with the Ethernet VPN (EVPN) Layer 2 ingress packet processing of Cisco Nexus 3600 Platform Switches and Cisco Nexus 9500-R Series Switching Platforms could allow an unauthenticated, adjacent attacker to trigger a Layer 2 traffic loop. This vulnerability is due to a logic error when processing a crafted Layer 2 ingress frame. An attacker could exploit this vulnerability by sending a stream of crafted Ethernet frames through the targeted device. A successful exploit could allow the attacker to cause a Layer 2 Virtual eXtensible LAN (VxLAN) traffic loop, which, in turn, could result in a denial of service (DoS) condition. This Layer 2 loop could oversubscribe the bandwidth on network interfaces, which would result in all data plane traffic being dropped. To exploit this vulnerability, the attacker must be Layer 2-adjacent to the affected device. Note: To stop active exploitation of this vulnerability, manual intervention is required to both stop the crafted traffic and flap all involved network interfaces. For additional assistance if a Layer 2 loop that is related to this vulnerability is suspected, contact the Cisco Technical Assistance Center (TAC) or the proper support provider.
Metrics
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco NX-OS Software | 9.2(3); 9.2(2v); 9.2(1); 9.2(2t); 9.2(3y); 9.3(2); 9.2(4); 9.3(1); 9.3(1z); 9.2(2); 9.3(3); 9.3(4); 9.3(5); 9.3(6); 9.3(5w); 9.3(7); 9.3(7k); 10.2(1); 9.3(7a); 9.3(8) |
References
Timeline
- Published
- Feb 25, 2026
- Last modified
- Jun 17, 2026
- NVD status
- Deferred