CVE-2023-25770Network attack vector

Remote code execution via unchecked endian conversion

Published Jul 13, 2023 · Updated Aug 2, 2024

Buffer overflow in Honeywell Experion PKS C300 Controller firmware allows remote attackers to execute code via crafted CDA messages. The ntoh library trusts the request-header size while reversing byte order, allowing a crafted size to overwrite static memory beyond the CDA message buffer. Network access to the controller is sufficient and no authentication or user interaction is required; exploitation can crash the controller or execute code.

CVSS severity9.8
Critical
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Buffer overflow in Honeywell Experion PKS C300 Controller firmware allows remote attackers to execute code via crafted CDA messages. The ntoh library trusts the request-header size while reversing byte order, allowing a crafted size to overwrite static memory beyond the CDA message buffer. Network access to the controller is sufficient and no authentication or user interaction is required; exploitation can crash the controller or execute code.

The record

CVE
CVE-2023-25770
Published
Jul 13, 2023
Updated
Aug 2, 2024
Vendor
Honeywell Technologies
Product
Experion PKS C300 Controller
Classifications
CWE-502, CAPEC-221, T0814, T0866
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 13, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=501.1 <=501.6hf8
  2. Affected versionversion=501.1 <=501.6HF8
  3. Affected versionversion=510.1 <=510.2hf12
  4. Affected versionversion=510.1 <=510.2HF12
  5. Affected versionversion=510.1 <=511.5TCU3
  6. Affected versionversion=511.1 <=511.5tcu3
  7. Affected versionversion=511.1 <=511.5TCU3
  8. Affected versionversion=520.1 <=520.1tcu4
  9. Affected versionversion=520.1 <=520.1TCU4
  10. Affected versionversion=520.2 <=520.2tcu2
  11. Affected versionversion=520.2 <=520.2TCU2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Honeywell Technologies · Experion PKS C300 Controllerversion=501.1 <=501.6hf8; version=501.1 <=501.6HF8; version=510.1 <=510.2hf12; version=510.1 <=510.2HF12; version=510.1 <=511.5TCU3; version=511.1 <=511.5tcu3; version=511.1 <=511.5TCU3; version=520.1 <=520.1tcu4; version=520.1 <=520.1TCU4; version=520.2 <=520.2tcu2; version=520.2 <=520.2TCU2

Published CVSS scores

7.5NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
9.8HoneywellCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CAPEC-221XML External Entities Blowup
T0814Denial of Service
T0866Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo