Cisco Nexus 3000 and 9000 Series Switches Layer 2 Ethernet Denial of Service Vulnerability
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
A vulnerability in the health monitoring diagnostics of Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, adjacent attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of specific Ethernet frames. An attacker could exploit this vulnerability by sending a sustained rate of crafted Ethernet frames to an affected device. A successful exploit could allow the attacker to cause the device to reload.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco NX-OS Software | 9.3(2); 9.3(1); 9.3(1z); 9.3(3); 9.3(4); 9.3(5); 9.3(6); 10.1(2); 10.1(1); 9.3(5w); 9.3(7); 9.3(7k); 10.2(1); 9.3(7a); 9.3(8); 10.2(1q); 10.2(2); 9.3(9); 10.1(2t); 10.2(3); 10.2(3t); 9.3(10); 10.2(2a); 10.3(1); 10.2(4); 10.3(2); 9.3(11); 10.3(3); 10.2(5); 9.3(12); 10.2(3v); 10.4(1); 10.3(99w); 10.2(6); 10.3(3w); 10.3(99x); 10.3(3o); 10.3(4); 10.3(3p); 10.3(4a); 10.4(2); 10.3(3q); 9.3(13); 10.3(5); 10.2(7); 10.4(3); 10.3(3x); 10.3(4g); 10.5(1); 10.2(8); 10.3(3r); 9.3(14); 10.3(4h) | — | No fix listed | CNA |
- Cisco NX-OS Software VendorCisco Affected 9.3(2); 9.3(1); 9.3(1z); 9.3(3); 9.3(4); 9.3(5); 9.3(6); 10.1(2); 10.1(1); 9.3(5w); 9.3(7); 9.3(7k); 10.2(1); 9.3(7a); 9.3(8); 10.2(1q); 10.2(2); 9.3(9); 10.1(2t); 10.2(3); 10.2(3t); 9.3(10); 10.2(2a); 10.3(1); 10.2(4); 10.3(2); 9.3(11); 10.3(3); 10.2(5); 9.3(12); 10.2(3v); 10.4(1); 10.3(99w); 10.2(6); 10.3(3w); 10.3(99x); 10.3(3o); 10.3(4); 10.3(3p); 10.3(4a); 10.4(2); 10.3(3q); 9.3(13); 10.3(5); 10.2(7); 10.4(3); 10.3(3x); 10.3(4g); 10.5(1); 10.2(8); 10.3(3r); 9.3(14); 10.3(4h) Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2025-20111
- 2026-10-03 Alias added: GHSA-q737-5cw3-3g78
References
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Sources
- CVE-2025-20111 · CVE Program
- CVE-2025-20111 · NVD
- FIRST EPSS
- GHSA-q737-5cw3-3g78 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences