CVE-2021-38395

Name: CVE-2021-38395
Creator: NVD / NIST
Published: 2022-10-28T02:15:16.857+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 0.87%

Last modified Jun 17, 2026

CVE-2021-38395 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Honeywell Experion PKS C200, C200E, C300, and ACE controllers are vulnerable to improper neutralization of special elements in output, which may allow an attacker to remotely execute arbitrary code and cause a denial-of-service condition.. EPSS estimates a 0.87% chance of exploitation in the next 30 days.

Description

Honeywell Experion PKS C200, C200E, C300, and ACE controllers are vulnerable to improper neutralization of special elements in output, which may allow an attacker to remotely execute arbitrary code and cause a denial-of-service condition.

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

0.87%

54.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Honeywell	C200 Firmware	All versions
Honeywell	C200e Firmware	All versions
Honeywell	C300 Firmware	All versions
Honeywell	Application Control Environment Firmware	All versions

References

https://www.cisa.gov/uscert/ics/advisories/icsa-21-278-04Mitigation, Third Party Advisory, US Government Resource
https://www.honeywellprocess.com/library/support/notifications/Customer/SN2021-02-22-01-Experion-C300-CCL.pdfProduct
https://www.cisa.gov/uscert/ics/advisories/icsa-21-278-04Mitigation, Third Party Advisory, US Government Resource
https://www.honeywellprocess.com/library/support/notifications/Customer/SN2021-02-22-01-Experion-C300-CCL.pdfProduct

Timeline

Published: Oct 28, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-38395?

How severe is CVE-2021-38395?

CVE-2021-38395 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.87% probability of exploitation in the next 30 days.

How do I fix CVE-2021-38395?

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-2021-38395?

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

Scan your code now

Source: NVD / NIST