CVE-2024-11609 Overview
CVE-2024-11609 is a stack-based buffer overflow [CWE-121] in the AutomationDirect C-More EA9 programming software. The flaw exists in the parser that processes EAP9 project files. The software fails to validate the length of user-supplied data before copying it into a fixed-length stack buffer. An attacker who tricks an operator or engineer into opening a crafted EAP9 file can execute arbitrary code in the context of the current process. This issue was originally tracked as ZDI-CAN-24772 and disclosed through the Zero Day Initiative as ZDI-24-1673.
Critical Impact
Successful exploitation yields arbitrary code execution on engineering workstations used to program C-More EA9 human-machine interface (HMI) panels, providing a foothold into operational technology (OT) networks.
Affected Products
- AutomationDirect C-More EA9 programming software and associated firmware for EA9-T6CL, EA9-T6CL-R, EA9-T8CL, EA9-T10CL, and EA9-T10WCL HMI panels
- AutomationDirect C-More EA9-T12CL, EA9-T15CL, and EA9-T15CL-R HMI panels and firmware
- AutomationDirect C-More EA9-RHMI remote HMI hardware and firmware
Discovery Timeline
- 2025-01-30 - CVE-2024-11609 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-11609
Vulnerability Analysis
The C-More EA9 programming software is used by control engineers to design HMI screens and download them to AutomationDirect panels on factory floors. The parser responsible for reading EAP9 project files contains a classic stack-based buffer overflow. Attacker-controlled data inside the file is copied into a fixed-size stack buffer without a bounds check. The overflow overwrites adjacent stack memory, including saved return addresses and structured exception handlers, enabling redirection of execution flow. Because the vulnerability triggers on file open, exploitation happens entirely on the engineering workstation and does not require network access to the target HMI.
Root Cause
The root cause is missing input validation on a length field or string element parsed from an EAP9 file. The parser trusts the file-supplied length and passes it into an unbounded copy operation targeting a stack allocation. This maps to CWE-121: Stack-based Buffer Overflow.
Attack Vector
Exploitation requires user interaction. An attacker must deliver a malicious EAP9 file to an operator, integrator, or control engineer via phishing, a shared project repository, a USB drive, or a compromised vendor supply channel. When the victim opens the file in the C-More EA9 programming software, the parser triggers the overflow and executes attacker-supplied shellcode in the context of the current user. No verified public proof-of-concept code is available for CVE-2024-11609. Refer to the Zero Day Initiative Advisory ZDI-24-1673 and the CERT VDE Bulletin on AutomationDirect EA9 for coordinated disclosure details.
Detection Methods for CVE-2024-11609
Indicators of Compromise
- Unexpected EAP9 project files arriving via email, chat, or removable media on engineering workstations that run C-More EA9 software
- Crashes or Windows Error Reporting events referencing the C-More EA9 programming executable when opening a project file
- Child processes spawned by the C-More EA9 programming software that are inconsistent with normal engineering workflows, such as cmd.exe, powershell.exe, or rundll32.exe
- Outbound network connections initiated by the C-More EA9 process shortly after a project file is opened
Detection Strategies
- Alert when the C-More EA9 programming process launches interpreters, script hosts, or LOLBins.
- Hunt for EAP9 files originating from untrusted sources such as internet downloads or external email attachments.
- Correlate application crash telemetry from engineering workstations with subsequent process-creation and network activity.
Monitoring Recommendations
- Monitor engineering workstations with an endpoint detection and response (EDR) agent that records process ancestry, module loads, and file provenance for the C-More EA9 executable.
- Log project file transfers into OT engineering zones and compare hashes against an approved allowlist.
- Baseline normal parent-child process relationships for OT engineering tools so that anomalous execution chains stand out.
How to Mitigate CVE-2024-11609
Immediate Actions Required
- Inventory all endpoints running the AutomationDirect C-More EA9 programming software and prioritize engineering workstations in production support roles.
- Apply the vendor-supplied update referenced in the CERT VDE Bulletin on AutomationDirect EA9 as soon as it is qualified for the environment.
- Restrict EAP9 file exchange to trusted internal repositories and block delivery of EAP9 attachments at the email gateway.
- Train control engineers to treat unsolicited or externally sourced project files as untrusted until validated.
Patch Information
AutomationDirect and CERT@VDE coordinated the disclosure. Users should consult the CERT VDE Bulletin on AutomationDirect EA9 and the Zero Day Initiative Advisory ZDI-24-1673 for the fixed software version and download instructions, then update all engineering workstations that handle C-More EA9 projects.
Workarounds
- Run the C-More EA9 programming software on a dedicated, network-segmented engineering workstation that is not used for email or general web browsing.
- Enforce application allowlisting so only signed and approved OT engineering tools can execute on engineering hosts.
- Enable exploit mitigations such as Data Execution Prevention (DEP), Address Space Layout Randomization (ASLR), and Control Flow Guard (CFG) system-wide via Windows Defender Exploit Guard.
- Require validation of project file origin and integrity, for example through cryptographic hashes or signed transfers, before opening any EAP9 file.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
