CVE-2021-40521

Name: CVE-2021-40521
Creator: NVD / NIST
Published: 2021-11-10T16:15:09.093+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 4.35%

Last modified Jun 17, 2026

CVE-2021-40521 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Airangel HSMX Gateway devices through 5.2.04 allow Remote Code Execution.. EPSS estimates a 4.35% chance of exploitation in the next 30 days.

Description

Airangel HSMX Gateway devices through 5.2.04 allow Remote Code Execution.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

4.35%

90.0th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Airangel	Hsmx-App-25 Firmware	<= 5.2.04
Airangel	Hsmx-App-100 Firmware	<= 5.2.04
Airangel	Hsmx-App-1000 Firmware	<= 5.2.04
Airangel	Hsmx-App-5000 Firmware	<= 5.2.04
Airangel	Hsmx-App-20000 Firmware	<= 5.2.04

References

http://etizazmohsin.com/hsmx.html#rceExploit, Third Party Advisory
https://airangel.com/hsmx-gateway/Product
http://etizazmohsin.com/hsmx.html#rceExploit, Third Party Advisory
https://airangel.com/hsmx-gateway/Product

Timeline

Published: Nov 10, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40521?

Airangel HSMX Gateway devices through 5.2.04 allow Remote Code Execution.

How severe is CVE-2021-40521?

CVE-2021-40521 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 4.35% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40521?

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-2021-40521?

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

Scan your code now

Source: NVD / NIST