CVE-2020-3399
Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family CAPWAP Denial of Service Vulnerability
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing 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 of an affected device. The vulnerability is due to insufficient input validation during CAPWAP packet processing. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device, resulting in a buffer over-read. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.6
Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family CAPWAP Denial of Service Vulnerability
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing 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 of an affected device. The vulnerability is due to insufficient input validation during CAPWAP packet processing. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device, resulting in a buffer over-read. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.
- Record
CVE-2020-3399- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - Weakness
- CWE-126
- Updated
- 2026-11-02
EUVDEUVD-2020-24670
8.6
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing 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 of an affected device. The vulnerability is due to insufficient input validation during CAPWAP packet processing. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device, resulting in a buffer over-read. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.
- Record
EUVD-2020-24670- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-v379-w98r-25cr No score
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol...
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing 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 of an affected device. The vulnerability is due to insufficient input validation during CAPWAP packet processing. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device, resulting in a buffer over-read. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.
- Record
GHSA-v379-w98r-25cr- Updated
- 2026-11-02
NVD
8.6
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing 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 of an affected device. The vulnerability is due to insufficient input validation during CAPWAP packet processing. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device, resulting in a buffer over-read. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.
- Record
CVE-2020-3399- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - CVSS 2.0
- 7.8 High
AV:N/AC:L/Au:N/C:N/I:N/A:C - Weakness
- CWE-126, CWE-125
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-3399 is a high vulnerability (CVSS 8.6) in Cisco Ios Xe Software, published September 24, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.36%, the 71st percentile. No source names a fixed version.