CVE-2021-37604

Name: CVE-2021-37604
Creator: NVD / NIST
Published: 2021-08-05T16:15:07.217+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.23%

Last modified Jun 17, 2026

CVE-2021-37604 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. In version 6.5 of Microchip MiWi software and all previous versions including legacy products, there is a possibility of frame counters being validated/updated prior to the message authentication. With this vulnerability in place, an attacker may increment the incoming frame counter values by injecting messages with a sufficiently large frame counter value and invalid payload. EPSS estimates a 1.23% chance of exploitation in the next 30 days.

Description

In version 6.5 of Microchip MiWi software and all previous versions including legacy products, there is a possibility of frame counters being validated/updated prior to the message authentication. With this vulnerability in place, an attacker may increment the incoming frame counter values by injecting messages with a sufficiently large frame counter value and invalid payload. This results in denial of service/valid packets in the network. There is also a possibility of a replay attack in the stack.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

1.23%

65.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-670

Affected Software

Vendor	Product	Versions
Microchip	Miwi	6.5

References

https://ww1.microchip.com/downloads/en/DeviceDoc/asf-release-notes-3.50.0.100-readme.pdfRelease Notes, Vendor Advisory
https://www.microchip.com/en-us/development-tools-tools-and-software/libraries-code-examples-and-more/advanced-software-framework-for-sam-devices#DownloadsVendor Advisory
https://www.microchip.com/en-us/products/wireless-connectivity/software-vulnerability-response/miwi-software-vulnerabilityVendor Advisory
https://www.microchip.com/en-us/products/wireless-connectivity/sub-ghz/miwi-protocolVendor Advisory
https://www.microchip.com/product-change-notifications/#/Vendor Advisory
https://ww1.microchip.com/downloads/en/DeviceDoc/asf-release-notes-3.50.0.100-readme.pdfRelease Notes, Vendor Advisory
https://www.microchip.com/en-us/development-tools-tools-and-software/libraries-code-examples-and-more/advanced-software-framework-for-sam-devices#DownloadsVendor Advisory
https://www.microchip.com/en-us/products/wireless-connectivity/software-vulnerability-response/miwi-software-vulnerabilityVendor Advisory
https://www.microchip.com/en-us/products/wireless-connectivity/sub-ghz/miwi-protocolVendor Advisory
https://www.microchip.com/product-change-notifications/#/Vendor Advisory

Timeline

Published: Aug 5, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-37604?

How severe is CVE-2021-37604?

CVE-2021-37604 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.23% probability of exploitation in the next 30 days.

How do I fix CVE-2021-37604?

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-2021-37604?

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

Scan your code now

Source: NVD / NIST