Cisco IOS XE Software Flexible NetFlow Version 9 Denial of Service Vulnerability
Priority MEDIUM 46CWE-20Published · Updated
Key facts
- Attack vector
- 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 · NVD. Fix status from CNA.
Summary
A vulnerability in the Flexible NetFlow Version 9 packet processor of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper validation of parameters in a Flexible NetFlow Version 9 record. An attacker could exploit this vulnerability by sending a malformed Flexible NetFlow Version 9 packet to the Control and Provisioning of Wireless Access Points (CAPWAP) data port of an affected device. An exploit could allow the attacker to trigger an infinite loop, resulting in a process crash that would cause a reload of the device.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0151 74th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- 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 IOS XE Software 16.10.1 | all versions | — | No fix listed | CNA |
- Cisco IOS XE Software 16.10.1 VendorCisco Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 22
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:ios_xe:16.10.1:*:*:*:*:*:*:* | 16.10.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.10.1a:*:*:*:*:*:*:* | 16.10.1a | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.10.1b:*:*:*:*:*:*:* | 16.10.1b | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.10.1e:*:*:*:*:*:*:* | 16.10.1e | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.10.1s:*:*:*:*:*:*:* | 16.10.1s | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.10.2:*:*:*:*:*:*:* | 16.10.2 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.11.1:*:*:*:*:*:*:* | 16.11.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.11.1a:*:*:*:*:*:*:* | 16.11.1a | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.11.1b:*:*:*:*:*:*:* | 16.11.1b | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.11.1c:*:*:*:*:*:*:* | 16.11.1c | Vulnerable | Cisco |
- cpe:2.3:o:cisco:ios_xe:16.10.1:*:*:*:*:*:*:* Versions 16.10.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.10.1a:*:*:*:*:*:*:* Versions 16.10.1a Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.10.1b:*:*:*:*:*:*:* Versions 16.10.1b Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.10.1e:*:*:*:*:*:*:* Versions 16.10.1e Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.10.1s:*:*:*:*:*:*:* Versions 16.10.1s Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.10.2:*:*:*:*:*:*:* Versions 16.10.2 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.11.1:*:*:*:*:*:*:* Versions 16.11.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.11.1a:*:*:*:*:*:*:* Versions 16.11.1a Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.11.1b:*:*:*:*:*:*:* Versions 16.11.1b Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.11.1c:*:*:*:*:*:*:* Versions 16.11.1c Vulnerable ·Cisco
Show 12 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:ios_xe:16.11.1s:*:*:*:*:*:*:* | 16.11.1s | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.12.1:*:*:*:*:*:*:* | 16.12.1 | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.12.1a:*:*:*:*:*:*:* | 16.12.1a | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.12.1c:*:*:*:*:*:*:* | 16.12.1c | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.12.1s:*:*:*:*:*:*:* | 16.12.1s | Vulnerable | Cisco |
| cpe:2.3:o:cisco:ios_xe:16.12.1t:*:*:*:*:*:*:* | 16.12.1t | Vulnerable | Cisco |
| cpe:2.3:h:cisco:catalyst_9800-40:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:catalyst_9800-80:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:catalyst_9800-cl:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:catalyst_9800-l:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:catalyst_9800-l-c:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:catalyst_9800-l-f:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:o:cisco:ios_xe:16.11.1s:*:*:*:*:*:*:* Versions 16.11.1s Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.12.1:*:*:*:*:*:*:* Versions 16.12.1 Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.12.1a:*:*:*:*:*:*:* Versions 16.12.1a Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.12.1c:*:*:*:*:*:*:* Versions 16.12.1c Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.12.1s:*:*:*:*:*:*:* Versions 16.12.1s Vulnerable ·Cisco
- cpe:2.3:o:cisco:ios_xe:16.12.1t:*:*:*:*:*:*:* Versions 16.12.1t Vulnerable ·Cisco
- cpe:2.3:h:cisco:catalyst_9800-40:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:catalyst_9800-80:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:catalyst_9800-cl:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:catalyst_9800-l:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:catalyst_9800-l-c:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:catalyst_9800-l-f:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-3221
- 2026-10-03 Alias added: GHSA-q65h-8wrc-fm43
References
More Cisco Ios Xe vulnerabilities
- TI-2023-06904 Cisco is providing an update for the ongoing investigation into observed exploitation of… KEVCVSS 3.1CRITICAL 10.0
- TI-2018-00122 Memory corruption in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
- TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
- TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
- TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
- TI-2017-04497 Memory corruption in Cisco IOS XE Software KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2020-3221 · CVE Program
- CVE-2020-3221 · NVD
- FIRST EPSS
- GHSA-q65h-8wrc-fm43 · 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