CVE-2020-3517
No exploitation reported by the sources we read.
- Published2020-08-27
- Fixed in4.1\(1c\) · 4.0\(4i\) · 3.2\(3o\)
- WeaknessCWE-476
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 in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated attacker to cause process crashes, which could result in a denial of service (DoS) condition on an affected device. The attack vector is configuration dependent and could be remote or adjacent. For more information about the attack vector, see the Details section of this advisory. The vulnerability is due to insufficient error handling when the affected software parses Cisco Fabric Services messages. An attacker could exploit this vulnerability by sending malicious Cisco Fabric Services messages to an affected device. A successful exploit could allow the attacker to cause a reload of an affected device, which could result in a DoS condition.
Timeline
dates in UTC- 2020-08-2716:15CVE 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-2020-3517?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-3517?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 |
|---|---|---|---|
| 4.1 | ≥ 4.1, < 4.1\(1c\) | 4.1\(1c\) | NVD |
| 4.0 | ≥ 4.0, < 4.0\(4i\) | 4.0\(4i\) | NVD |
| 3.2 | < 3.2\(3o\) | 3.2\(3o\) | NVD |
| 6.0 | = 6.0\(2\)a3\(1\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a3\(2\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a3\(4\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a4\(1\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a4\(2\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a4\(3\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a4\(4\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a4\(5\) | no fix published | NVD |
| 6.0 | = 6.0\(2\)a4\(6\) | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 2.2 | ≥ 2.2, < 2.2.1.70 | 2.2.1.70 | NVD |
| 2.1 | ≥ 2.1, < 2.1.1.86 | 2.1.1.86 | NVD |
| 2.0 | ≥ 2.0, < 2.0.1.153 | 2.0.1.153 | NVD |
| 1.1 | ≥ 1.1, < 1.1.4.179 | 1.1.4.179 | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Cisco nx-os to 4.1\(1c\) · 4.0\(4i\) · 3.2\(3o\)
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:C/C:N/I:N/A:H
- Published
- 2020-08-27
- Last Modified
- 2026-06-17
- NVD status
- Undergoing Analysis
Frequently asked questions
What is CVE-2020-3517?
Is CVE-2020-3517 actively exploited?
What is the CVSS score for CVE-2020-3517?
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Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.