Cisco Nexus 3000 and 9000 Series Border Gateway Protocol Denial of Service Vulnerability
Published May 20, 2026
6.8
MEDIUMCVSS 3.1
EPSS 0.47%
Description
A vulnerability in the Border Gateway Protocol (BGP) enforce-first-as feature of Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, remote attacker to trigger BGP peer flaps, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect parsing of a transitive BGP attribute. An attacker could exploit this vulnerability by sending a crafted BGP update through an established BGP peer session. If the update propagates to an affected device, it could cause the device to drop the BGP session and flap with the BGP peer that is forwarding this update, resulting in a DoS condition.
Affected products
-
Affected
- 10.2(1)
- 10.2(1q)
- 10.2(2)
- 10.2(2a)
- 10.2(3)
- 10.2(3t)
- 10.2(3v)
- 10.2(4)
- 10.2(5)
- 10.2(6)
- 10.2(7)
- 10.2(8)
- 10.2(9)
- 10.3(1)
- 10.3(2)
- 10.3(3)
- 10.3(3o)
- 10.3(3p)
- 10.3(3q)
- 10.3(3r)
- 10.3(3w)
- 10.3(3x)
- 10.3(4)
- 10.3(4a)
- 10.3(4g)
- 10.3(4h)
- 10.3(5)
- 10.3(6)
- 10.3(7)
- 10.3(8)
- 10.3(99w)
- 10.3(99x)
- 10.4(1)
- 10.4(2)
- 10.4(3)
- 10.4(4)
- 10.4(4g)
- 10.4(5)
- 10.4(6)
- 10.5(1)
- 10.5(2)
- 10.5(3)
- 10.5(3e)
- 10.5(3o)
- 10.5(3p)
- 10.5(3s)
- 10.5(3t)
- 10.6(1)
- 10.6(1s)
Default status is the baseline for the product. Each version can override it (patched versions can be marked unaffected).
| Vendor | Product | Default status | Versions |
|---|---|---|---|
| Cisco | Cisco NX-OS Software | unknown | Affected
|
No data.
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
References (2)
Change history (0)
No recorded changes yet.
CVE.org / MITRE
CISA Vulnrichment
Red Hat
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GitHub
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