CVE-2021-1230
No exploitation reported by the sources we read.
- Published2021-02-24
- WeaknessCWE-233
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
A vulnerability with the Border Gateway Protocol (BGP) for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a routing process to crash, which could lead to a denial of service (DoS) condition. This vulnerability is due to an issue with the installation of routes upon receipt of a BGP update. An attacker could exploit this vulnerability by sending a crafted BGP update to an affected device. A successful exploit could allow the attacker to cause the routing process to crash, which could cause the device to reload. This vulnerability applies to both Internal BGP (IBGP) and External BGP (EBGP). Note: The Cisco implementation of BGP accepts incoming BGP traffic from explicitly configured peers only. To exploit this vulnerability, an attacker would need to send a specific BGP update message over an established TCP connection that appears to come from a trusted BGP peer.
Timeline
dates in UTC- 2021-02-2420:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-1230?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-1230?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 12.0 | = 12.0\(1m\) | no fix published | NVD |
| 12.0 | = 12.0\(1n\) | no fix published | NVD |
| 12.0 | = 12.0\(1o\) | no fix published | NVD |
| 12.0 | = 12.0\(1p\) | no fix published | NVD |
| 12.0 | = 12.0\(1q\) | no fix published | NVD |
| 12.0 | = 12.0\(1r\) | no fix published | NVD |
| 12.0 | = 12.0\(2f\) | no fix published | NVD |
| 12.0 | = 12.0\(2g\) | no fix published | NVD |
| 12.0 | = 12.0\(2h\) | no fix published | NVD |
| 12.0 | = 12.0\(2l\) | no fix published | NVD |
| 12.0 | = 12.0\(2m\) | no fix published | NVD |
| 12.0 | = 12.0\(2n\) | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
Advisories and patches
- tools.cisco.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2021-02-24
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-1230?
Is CVE-2021-1230 actively exploited?
What is the CVSS score for CVE-2021-1230?
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