CVE-2020-3399

Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family CAPWAP Denial of Service Vulnerability

HIGH
8.6
CVSS Score
Published: September 24, 2020 at 06:02 PM UTC
Updated: June 17, 2026 at 03:18 AM UTC
7 products affected across 1 vendorIOS XeCatalyst 9800-LCatalyst 9800-80

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Severity
HIGH8.6
Exploit prediction
EPSS 1%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

cisco-catalyst-9800-40 (environment) · cisco-catalyst-9800-80 (environment) · cisco-catalyst-9800-cl (environment) · cisco-catalyst-9800-l (environment) · cisco-catalyst-9800-l-c (environment) · cisco-catalyst-9800-l-f (environment)
All versions
All versions
All versions
All versions
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.6HIGHcisco
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-126CWE-125

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