Skip to content
Fencer Vulns
high 8.6

CVE-2025-2521 json

Lack of indexes’ validation against buffer borders leads to remote code execution.

published 2025-07-10 15 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-21067

cvss
8.6
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits
0
none known

Summary

The Honeywell Experion PKS and OneWireless WDM contains a Memory Buffer vulnerability in the component Control Data Access (CDA). An attacker could potentially exploit this vulnerability, leading to an Overread Buffers, which could result in improper index validation against buffer borders leading to remote code execution.

Honeywell recommends updating to the most recent version of Honeywell Experion PKS:

520.2 TCU9 HF1 and 530.1 TCU3 HF1 and OneWireless: 322.5 and 331.1.

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.The OneWireless WDM affected versions are 322.1 through 322.4 and 330.1 through 330.3.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-25-205-03 updated cvss 8.6

Honeywell Experion PKS (Update A)

  • Honeywell Experion PKS <R520.2_TCU9_Hot_Fix_1, <R530_TCU3_Hot_Fix_1
    affected: vendor fix process.honeywell.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

cisa ICSA-25-247-01 updated cvss 8.6

Honeywell OneWireless Wireless Device Manager (WDM)

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
15 mo ago

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

Affected products

  • Honeywell C300 PCNT02
  • Honeywell C300 PCNT05
  • Honeywell FIM4
  • Honeywell FIM8
  • Honeywell UOC
  • Honeywell CN100
  • Honeywell HCA
  • Honeywell C300PM
  • Honeywell C200E
  • Honeywell Wireless Device Manager

Classification

Weakness
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.