Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family Improper Access Control Vulnerability

published 2020-09-24 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-24689

cvss: 4.7; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

A vulnerability in Cisco IOS XE Wireless Controller Software for Cisco Catalyst 9800 Series Routers could allow an unauthenticated, adjacent attacker to send ICMPv6 traffic prior to the client being placed into RUN state. The vulnerability is due to an incomplete access control list (ACL) being applied prior to RUN state. An attacker could exploit this vulnerability by connecting to the associated service set identifier (SSID) and sending ICMPv6 traffic. A successful exploit could allow the attacker to send ICMPv6 traffic prior to RUN state.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 23 mo ago (2024-11-13)

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.0	4.7	CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD	3.1	4.7	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD	2.0	3.3	AV:A/AC:L/Au:N/C:N/I:P/A:N

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-284 Improper Access Control

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-icmpv6-qb9eYyCR
vendor-advisory

Sources

CVE List CVE-2020-3418
NVD CVE-2020-3418

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Summary