CVE-2025-3947: Honeywell c200e

High severity, CVSS 8.2. EPSS: 0.3% chance of exploitation in the next 30 days.

The Honeywell Experion PKS contains an Integer Underflow vulnerability in the component Control Data Access (CDA). An attacker could potentially exploit this vulnerability, leading to Input Data Manipulation, which could result in improper integer data value checking during subtraction leading to a denial of service. Honeywell recommends updating to the most recent version of Honeywell Experion PKS:520.2 TCU9 HF1 and 530.1 TCU3 HF1. The affected Experion PKS products are C300 PCNT02, C300 PCNT05, FIM4, FIM8, UOC, CN100, HCA, C300PM, and C200E. The Experion PKS versions affected are from 520.1 through 520.2 TCU9 and from 530 through 530 TCU3.

Affected products

• Honeywell c200e: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell c300 PCNT02: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell c300 PCNT05: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell c300pm: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell CN100: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell FIM4: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell FIM8: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell Hca: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3
• Honeywell Uoc: from 520.1, up to and including 520.2 TCU9; from 530, up to and including 530 TCU3

Published 2025-07-10. Last modified 2026-06-17.