CVE-2020-3231

Name: CVE-2020-3231
Creator: NVD / NIST
Published: 2020-06-03T18:15:21.09+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.7/10EPSS 0.45%

Last modified Jun 17, 2026

CVE-2020-3231 is a medium-severity vulnerability rated 4.7/10 on the CVSS scale. A vulnerability in the 802.1X feature of Cisco Catalyst 2960-L Series Switches and Cisco Catalyst CDB-8P Switches could allow an unauthenticated, adjacent attacker to forward broadcast traffic before being authenticated on the port. The vulnerability exists because broadcast traffic that is received on the 802.1X-enabled port is mishandled. EPSS estimates a 0.45% chance of exploitation in the next 30 days.

Description

A vulnerability in the 802.1X feature of Cisco Catalyst 2960-L Series Switches and Cisco Catalyst CDB-8P Switches could allow an unauthenticated, adjacent attacker to forward broadcast traffic before being authenticated on the port. The vulnerability exists because broadcast traffic that is received on the 802.1X-enabled port is mishandled. An attacker could exploit this vulnerability by sending broadcast traffic on the port before being authenticated. A successful exploit could allow the attacker to send and receive broadcast traffic on the 802.1X-enabled port before authentication.

Metrics

CVSS 3.1

4.7/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

EPSS Probability

0.45%

36.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Ios	15.2\(5\)e2
Cisco	Ios	15.2\(5\)ex
Cisco	Ios	15.2\(5a\)e
Cisco	Ios	15.2\(5b\)e
Cisco	Ios	15.2\(5c\)e
Cisco	Ios	15.2\(6\)e
Cisco	Ios	15.2\(6\)e0c
Cisco	Ios	15.2\(6\)e1
Cisco	Ios	15.2\(6\)e1a
Cisco	Ios	15.2\(6\)e1s
Cisco	Ios	15.2\(6\)e2
Cisco	Ios	15.2\(6\)e2b
Cisco	Ios	15.2\(6\)e3
Cisco	Ios	15.2\(6\)e4
Cisco	Ios	15.2\(7\)e
Cisco	Ios	15.2\(7\)e0a
Cisco	Ios	15.2\(7\)e0b
Cisco	Ios	15.2\(7\)e0s
Cisco	Ios	15.2\(7a\)e0b
Cisco	Ios	15.2\(7b\)e0b
Cisco	Ios	15.3\(3\)jaa1
Cisco	Ios	15.3\(3\)jpj

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-c2960L-DpWA9Re4Patch, Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-c2960L-DpWA9Re4Patch, Vendor Advisory

Timeline

Published: Jun 3, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-3231?

How severe is CVE-2020-3231?

CVE-2020-3231 has a CVSS score of 4.7/10 (MEDIUM severity). The EPSS model estimates a 0.45% probability of exploitation in the next 30 days.

How do I fix CVE-2020-3231?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-3231?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST