CVE-2020-3527

Name: CVE-2020-3527
Creator: NVD / NIST
Published: 2020-09-24T18:15:21.807+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.6/10EPSS 1.37%

Last modified Jun 17, 2026

CVE-2020-3527 is a high-severity vulnerability rated 8.6/10 on the CVSS scale. A vulnerability in the Polaris kernel of Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to crash the device. The vulnerability is due to insufficient packet size validation. EPSS estimates a 1.37% chance of exploitation in the next 30 days.

Description

A vulnerability in the Polaris kernel of Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to crash the device. The vulnerability is due to insufficient packet size validation. An attacker could exploit this vulnerability by sending jumbo frames or frames larger than the configured MTU size to the management interface of this device. A successful exploit could allow the attacker to crash the device fully before an automatic recovery.

Metrics

CVSS 3.1

8.6/10

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

EPSS Probability

1.37%

68.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Ios Xe	>= 16.9.0, < 16.9.5
Cisco	Ios Xe	>= 16.12.0, < 16.12.3

References

Timeline

Published: Sep 24, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-3527?

How severe is CVE-2020-3527?

CVE-2020-3527 has a CVSS score of 8.6/10 (HIGH severity). The EPSS model estimates a 1.37% probability of exploitation in the next 30 days.

How do I fix CVE-2020-3527?

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-2020-3527?

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

Scan your code now

Source: NVD / NIST