CVE-2022-26419

Executive Summary

CVE-2022-26419 is a stack-based buffer overflow vulnerability affecting Omron CX-Position versions 2.5.3 and prior. The flaw is triggered when the application parses a specially crafted project file, enabling a local attacker to achieve arbitrary code execution on the target system. Given that the attack vector is local and requires user interaction (opening a malicious file), the threat primarily targets engineering workstations used in industrial control system (ICS) environments. With a CVSS score of 7.8 (High), successful exploitation could fully compromise the host, potentially providing a foothold for lateral movement into OT networks.

Technical Analysis

The NVD description for CVE-2022-26419 is sparse but identifies a critical flaw class: multiple stack-based buffer overflow conditions exist during the parsing of a specific project file format. The CNA title references "Rockwell Automation Studio 5000 Logix Designer Code Injection," which appears to be a misattribution or cross-referencing error in the CNA metadata; the NVD description clearly states the affected product is Omron CX-Position.

Vulnerability Mechanism

Stack-based buffer overflows occur when a program writes data to a fixed-size stack buffer without adequate bounds checking. In this case, the CX-Position application parses project files containing structured data (likely position/axis control configuration data). When the parser encounters a field whose content exceeds the size of the destination stack buffer, it writes beyond the buffer boundary, corrupting adjacent stack memory — including the saved return address.

Because the description states "multiple" conditions exist, it is plausible that several different fields within the project file format are vulnerable, each requiring separate bounds-checking fixes. An attacker controlling the file contents can therefore:

1. Overwrite the saved return address on the stack.
2. Redirect execution to attacker-controlled memory (e.g., shellcode embedded in the file, or a ROP chain).
3. Achieve arbitrary code execution with the privileges of the user running CX-Position.

Attack Surface

The attack surface is the project file parser. CX-Position project files are typically shared between engineers or reused across installations. An attacker would need to deliver a malicious project file to the victim via:

• Email attachment
• USB drive
• Network share
• Industrial control system documentation or support portals

Since the vulnerability requires local execution (the file must be opened by CX-Position on the victim's machine), the attack is classified as Local (AV:L) with User Interaction required (UI:R) — the victim must explicitly open the crafted file.

Code-Level Considerations

Insufficient technical detail is available in public sources to identify the exact parsing functions, buffer sizes, or vulnerable fields. No function names or class names are disclosed in the NVD description or CNA title. The vulnerability class (CWE-121, Stack-based Buffer Overflow) is clearly established, but implementation specifics remain proprietary. Security researchers with access to the software would need to reverse-engineer the parser to locate the exact vulnerable code paths.

Exploitation Scenarios

Step 1 — Reconnaissance/Target Identification: The target is an engineering workstation running Omron CX-Position 2.5.3 or earlier. Attackers may identify potential victims through:

• LinkedIn profiles listing CX-Position as a skill
• ICS/OT focused job boards and forums
• Corporate network enumeration (if the attacker already has network access)
• Social engineering targeting of control engineers

Step 2 — Triggering the Flaw: The attacker crafts a malicious project file (.cxp or other proprietary extension) containing oversized data in one or more fields that are parsed into fixed-size stack buffers. The file is delivered to the victim via email, USB, or a compromised file-sharing platform. When the victim opens the project file in CX-Position, the parser reads the malformed field and triggers a stack buffer overflow.

Step 3 — Payload/Execution Method: At the vulnerability-class level, the attacker's payload would need to:

• Overwrite the saved return address on the stack
• Redirect execution to shellcode embedded within the project file itself (since stack protection may be absent on older Windows-based ICS software)
• Alternatively, use a ROP chain to bypass DEP if enabled

The shellcode would execute with the privileges of the logged-in user. Since CX-Position is engineering software, it is likely run with administrative privileges on OT engineering workstations.

Note: No public PoC is available; the attack chain is inferred from the vulnerability class and standard stack overflow exploitation techniques.

Step 4 — Post-Exploitation Impact: Once arbitrary code execution is achieved, the attacker can:

• Install persistence mechanisms (e.g., scheduled tasks, services)
• Exfiltrate project files containing PLC logic, IP addresses, and credential material
• Deploy a RAT or remote access tool for persistent access
• Pivot to other systems on the OT network, including PLCs and HMIs
• Potentially disrupt operations if the compromised workstation has engineering access to live control systems

Impact Assessment

CVSS Analysis (Score: 7.8, High):

• Attack Vector: Local (AV:L) — attacker needs local access or social engineering to deliver the file
• Attack Complexity: Low (AC:L) — no special conditions beyond the victim opening the file
• Privileges Required: None (PR:N) — no prior authentication needed; a low-privileged user can trigger it
• User Interaction: Required (UI:R) — victim must open the crafted file
• Confidentiality/Integrity/Availability Impact: All High (C:H/I:H/A:H) — full system compromise

Business Impact:

• Operational Disruption: A compromised engineering workstation can be used to upload malicious logic to PLCs, halt production lines, or manipulate process parameters.
• Intellectual Property Theft: CX-Position project files contain proprietary machine configurations, control algorithms, and potentially process secrets.
• Regulatory Risk: For critical infrastructure operators, a successful ICS-targeted attack may trigger regulatory notification requirements (e.g., NIS Directive, CFATS).
• Financial Loss: Downtime in industrial environments typically costs thousands of dollars per hour.

Blast Radius: The immediate blast radius is the single engineering workstation. However, in OT environments, engineering workstations are high-value targets because they hold credentials and network routes to PLCs. A compromised engineering workstation can lead to full compromise of the control network segment.

Detection Guidance

Sigma Rule

title: Potential Exploitation of Omron CX-Position Stack Buffer Overflow (CVE-2022-26419)
id: 8b3f7c2e-9d4a-4f6b-8c1e-5a2d9f3b7e61
status: experimental
description: Detects abnormal process behavior associated with CX-Position parsing malformed project files
author: Valtersit Threat Intelligence
date: 2024-01-15
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2022-26419
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        Image|endswith: '\CX-Position.exe'
        CommandLine|contains: 
            - '.cxp'
            - '.cxs'
    condition: selection
falsepositives:
    - Legitimate use of CX-Position to open standard project files
level: medium
tags:
    - attack.execution
    - attack.t1203
    - cve.2022.26419

YARA Rule

rule CVE_2022_26419_CXPosition_Malicious_Project
{
    meta:
        author = "Valtersit Threat Intelligence"
        description = "Detects patterns consistent with stack overflow payloads in CX-Position project files"
        cve = "CVE-2022-26419"
        date = "2024-01-15"
    strings:
        $shellcode_1 = { 90 90 90 90 90 90 90 90 }  // NOP sled
        $shellcode_2 = { 31 C0 50 68 2E 65 78 65 68 63 6D 64 20 6A 01 58 }  // Common exec shellcode pattern
        $ret_addr = { FF E0 }  // JMP EAX
        $ret_addr2 = { FF E4 }  // JMP ESP
        $cxp_magic = { 43 58 50 00 }  // "CXP\0"
    condition:
        uint32(0) == 0x43585000 or  // "CXP" file header
        ($cxp_magic and (any of ($shellcode_*) or any of ($ret_addr*)))
}

Note: The above YARA rule is speculative; actual file format magic bytes may differ. Network defenders should validate against legitimate sample files.

Suricata IDS Rule

alert http any any -> $HOME_NET any (msg:"CVE-2022-26419 Potential CX-Position Malicious Project File Download"; flow:established,to_client; file.magic:"CXP"; file.name:/.*\.(cxp|cxs)$/i; classtype:attempted-user; sid:60026419; rev:1; metadata:created_at 2024_01_15, updated_at 2024_01_15, cve 2022_26419;)

Additional Suricata Rule for SMB File Transfer

alert smb any any -> any any (msg:"CVE-2022-26419 CX-Position Project File Transfer via SMB"; content:"|00|"; file.name:/.*\.(cxp|cxs)$/i; flow:established,to_server; classtype:attempted-user; sid:60026420; rev:1; metadata:created_at 2024_01_15, cve 2022_26419;)

Elastic Detection (EQL)

process where event.action == "start" and
  process.name == "CX-Position.exe" and
  (process.args : "*.cxp" or process.args : "*.cxs") and
  not user.domain == "DOMAIN-SERVICE-ACCOUNT"  // Tune to exclude known-good automation accounts

Alternative Elastic Detection — File Corruption/Hang

file where event.module == "endpoint" and
  file.name : "*.cxp" and
  file.size > 50000000  // Abnormally large project file

Splunk SPL Query

index=windows sourcetype=ProcessCreation
| where Image="*\\CX-Position.exe"
| search CommandLine="*.cxp" OR CommandLine="*.cxs"
| table _time, host, user, Image, CommandLine, ParentImage
| stats count by host, user, CommandLine

Supplemental Splunk Detection

index=windows sourcetype=XmlWinEventLog:Microsoft-Windows-AppLocker/Operational
| search "CX-Position*"
| table _time, host, user, EventCode, FilePath

Wazuh OSSEC Rule

<group name="ics,">
  <rule id="100264" level="8">
    <decoded_as>syscheck</decoded_as>
    <field name="file">.*\.(cxp|cxs)$</field>
    <description>CX-Position project file detected. Investigate for CVE-2022-26419 exploitation.</description>
    <group>cve_2022_26419</group>
  </rule>

  <rule id="100265" level="10">
    <if_sid>100264</if_sid>
    <regex>\.cxp|\.cxs</regex>
    <description>CVE-2022-26419: CX-Position project file opened with user privileges. Verify legitimacy.</description>
    <group>cve_2022_26419</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 2/4 — CLAIMED (single source claims patch; not independently confirmed)

1) Immediate Mitigations

• Application Whitelisting: Use AppLocker or similar tools to restrict CX-Position execution to authorized users and approved directories.
• File Extension Control: Implement email filtering to block .cxp and .cxs attachments from untrusted senders.
• USB Policy: Disable USB mass storage devices on engineering workstations unless explicitly approved.
• User Awareness: Train engineering staff on the risk of opening project files from unverified sources, especially files received via email or shared networks.
• User Privilege Reduction: Run CX-Position with least-privilege user accounts instead of administrative accounts.
• Network Segmentation: Place engineering workstations in a separate VLAN with restricted access to the corporate network.

2) Patch/Upgrade Steps

• Official Fix: Upgrade to Omron CX-Position version 2.5.4. This version is available exclusively through the "Auto Update" function, which requires a valid maintenance/support contract.
• Contact: Reach out to Omron technical support or an authorized Omron representative to coordinate the upgrade.
• Validate: After upgrading, verify the version number and confirm the software functions correctly with existing project files.
• Backup: Maintain a rollback procedure against the previous version in case of compatibility issues.

3) Long-Term Hardening

• Endpoint Protection: Deploy EDR solutions on all OT engineering workstations with behavior-based detection for abnormal process execution patterns.
• File Integrity Monitoring: Implement FIM on project file directories to detect unauthorized file modifications or additions.
• Patch Management Program: Establish a formal patch lifecycle for all ICS/OT software, including timely tracking of vendor advisories from Omron and other ICS vendors (ICS-CERT, CISA).
• Secure File Transfer: Use encrypted, authenticated file transfer mechanisms (e.g., SFTP, signed archives) for all exchange of project files.
• Vulnerability Scanning: Include CX-Position and other engineering tools in regular vulnerability assessments.
• Incident Response Plan: Develop and test an IR playbook specific to OT workstation compromise scenarios.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2022-26419
2. CNA Advisory: Rockwell Automation / Omron — CNA title references "Rockwell Automation Studio 5000 Logix Designer Code Injection" (note: NVD description identifies Omron CX-Position as the affected product; verify vendor advisory for authoritative guidance)
3. Omron Support Portal: https://www.ia.omron.com/support/ (Contact for version 2.5.4 update information)
4. CISA ICS Advisories: Monitor https://www.cisa.gov/ics/advisories for related Omron advisories
5. EPSS Data: https://www.first.org/epss/ (EPSS score: 0.01985, 78.7th percentile)

Threat Actor Campaigns & Exploit-in-the-Wild Evidence:

• CVE-2022-26419 is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog.
• No public evidence of exploitation in the wild has been identified as of the writing of this report.
• No public exploit code or PoC exists at this time.
• The EPSS score of 0.01985 (78.7th percentile) indicates this vulnerability is actively being monitored by the exploit prediction community, but the absolute probability of exploitation remains low.