What’s Vulnerable › Vulnerabilities

CVE-2021-38399: Honeywell Experion PKS and ACE Controllers Relative Path Traversal

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2022-10-28 · updated 2026-06-17
• Weakness: CWE-23

Description

Honeywell Experion PKS C200, C200E, C300, and ACE controllers are vulnerable to relative path traversal, which may allow an attacker access to unauthorized files and directories.

Affected products

• Honeywell Application Control Environment Firmware: all versions
• Honeywell C200 Firmware: all versions
• Honeywell C200E Firmware: all versions
• Honeywell C300: all versions

References

• https://www.cisa.gov/uscert/ics/advisories/icsa-21-278-04
• https://www.honeywellprocess.com/library/support/notifications/Customer/SN2021-02-22-01-Experion-C300-CCL.pdf
• https://www.cisa.gov/uscert/ics/advisories/icsa-21-278-04
• https://www.honeywellprocess.com/library/support/notifications/Customer/SN2021-02-22-01-Experion-C300-CCL.pdf

Get alerted when CVE-2021-38399 or the next vulnerability affects your stack