How severe is CVE-2020-3418?

CVE-2020-3418 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-3418 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3418?

CVE-2020-3418 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3418?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-3418 published?

CVE-2020-3418 was published on 2020-09-24 and last updated on 2026-06-17.

CVE-2020-3418

CVE-2020-3418 is a medium-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 4.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-284.

Key facts

Severity: Medium (CVSS 3.x base score 4.7)
CVSS v2: 3.3
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Cisco Ios Xe
Published: 2020-09-24
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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. 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.
How severe is CVE-2020-3418?: CVE-2020-3418 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-3418 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3418?: CVE-2020-3418 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3418?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-3418 published?: CVE-2020-3418 was published on 2020-09-24 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-icmpv6-qb9eYyCR

Affected products (1)

cpe:2.3:o:cisco:ios_xe:17.1.1:*:*:*:*:*:*:*

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