TI-2021-16003 Aliases CVE-2021-38399 GHSA-xh3f-3c4f-cgh5

Honeywell Experion PKS and ACE Controllers Relative Path Traversal

MEDIUM 41CWE-23Published 2022-10-28 · Updated 2025-04-16

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-23 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00927 60th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Honeywell	Experion PKS	C200; C200E; C300; ACE controllers	—	No fix listed	CNA

Experion PKS VendorHoneywell Affected C200; C200E; C300; ACE controllers Fixed in — No fix listed CNA

CPE configurations NVD · 8

CPE	Versions	Role	Vendor
cpe:2.3:o:honeywell:c200_firmware:-:::::::*	not specified by NVD	Vulnerable	Honeywell
cpe:2.3:h:honeywell:c200:-:::::::*	not specified by NVD	Running on	Honeywell
cpe:2.3:o:honeywell:c200e_firmware:-:::::::*	not specified by NVD	Vulnerable	Honeywell
cpe:2.3:h:honeywell:c200e:-:::::::*	not specified by NVD	Running on	Honeywell
cpe:2.3:o:honeywell:c300_firmware:-:::::::*	not specified by NVD	Vulnerable	Honeywell
cpe:2.3:h:honeywell:c300:-:::::::*	not specified by NVD	Running on	Honeywell
cpe:2.3:o:honeywell:application_control_environment_firmware:-:::::::*	not specified by NVD	Vulnerable	Honeywell
cpe:2.3:h:honeywell:application_control_environment:-:::::::*	not specified by NVD	Running on	Honeywell

cpe:2.3:o:honeywell:c200_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Honeywell
cpe:2.3:h:honeywell:c200:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Honeywell
cpe:2.3:o:honeywell:c200e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Honeywell
cpe:2.3:h:honeywell:c200e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Honeywell
cpe:2.3:o:honeywell:c300_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Honeywell
cpe:2.3:h:honeywell:c300:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Honeywell
cpe:2.3:o:honeywell:application_control_environment_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Honeywell
cpe:2.3:h:honeywell:application_control_environment:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Honeywell

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-38399
2026-10-03 Alias added: GHSA-xh3f-3c4f-cgh5

References

Advisory 1

https://www.cisa.gov/uscert/ics/advisories/icsa-21-278-04

Other 1

https://www.honeywellprocess.com/library/support/notifications/Customer/SN2021-02-22-01-Experion-C300-CCL.pdf

TI-2021-16001 Honeywell Experion PKS and ACE Controllers Unrestricted Upload of File with Dangerous Type CVSS 3.1CRITICAL 10.0
TI-2021-15999 Honeywell Experion PKS and ACE Controllers Injection CVSS 3.1CRITICAL 9.8

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences