SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-3418

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.

MEDIUM 4.7EPSS 0.41%

Does this matter?

Lower severity and a low EPSS score (0.41%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
4.7 MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
EPSS
0.41% probability · 35th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-284
Affected
cisco/ios xe
Source
psirt@cisco.com
EPSS trend
0%3%5%26 October 2026: 0.41%26 October 202626 October 2026

EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.