CVE-2022-26417 — Threat Intelligence Report

Vendor/Product: Omron CX-Position
CNA Title: Rockwell Automation Studio 5000 Logix Designer Use After Free
Publication Date: Unknown (CVE assigned 2022)
Report Classification: Technical Threat Intelligence — Enterprise Distribution

Executive Summary

CVE-2022-26417 is a use-after-free memory corruption vulnerability in Omron CX-Position versions 2.5.3 and prior. The flaw is triggered when processing a specifically crafted project file, allowing a remote or local attacker to achieve arbitrary code execution on the engineering workstation. With a CVSS score of 7.8 (High), successful exploitation requires the target user to open a malicious project file, making this a client-side attack vector targeting ICS/OT engineering environments. It is critical to note the expected patch (v2.5.4) is only provided via Auto Update to paying users, and no public proof-of-concept or exploitation-in-the-wild evidence has been observed to date.

Technical Analysis

The vulnerability in Omron CX-Position (versions 2.5.3 and prior) is a classic use-after-free (UAF) memory corruption issue, classified under CWE-416. A use-after-free condition arises when a program continues to reference a memory region after it has been freed, causing the pointer to become "dangling." When the freed memory block is subsequently reallocated (for instance, by another object or attacker-controlled data), the dangling pointer can read or write to this new allocation. An attacker can shape the heap in ways that lead to arbitrary memory read/write primitives, potentially escalating to full arbitrary code execution.

Attack Surface and Vector: The attack vector is local (AV:L) with user interaction (UI:R) — the victim must open a malicious project file. The file format is the proprietary Omron CX-Position project format (often packaged within CX-One suite project structures). No prior authentication or special privileges are required (PR:N) to trigger the vulnerability — merely the act of opening the crafted file. The complexity of the attack is low (AC:L), meaning the attacker does not need to overcome unusual race conditions or specific heap grooming beyond what is achievable with modest file-crafting effort.

Code-Level Perspective: The specific code path is not disclosed in public data. Based on CWE-416 characteristics, the vulnerability likely resides in the file-parsing module that loads project configuration data into memory structures. When a malformed but structurally valid project file is processed, a pointer to an object may be freed prematurely (e.g., during error handling or object teardown), and the subsequent access to that freed memory triggers the fault. The attacker-controlled file content can influence heap layout, enabling the freed memory to be repopulated with attacker-influenced data structures that cause instructions to be redirected to malicious payloads.

CNA Context — Rockwell Association: The CNA is Rockwell Automation, indicating the vulnerability was at least discovered or coordinated within the broader Rockwell/ICS ecosystem. It is plausible the same root issue affects multiple products sharing a common code base, but no further technical evidence of cross-product impact is available; treat this as unconfirmed.

Patch Gating Concern: The vendor mitigation is version 2.5.4, but it is explicitly limited to paying customers via the Auto Update function. This creates a significant exposure window for non-paying or unlicensed users of CX-Position, who may not have eligibility for the fix. The patch has not been independently verified to resolve the reported UAF condition (patch confidence 2/4).

Exploitation Scenarios

No public PoC is available; the attack chain is inferred from the vulnerability class (use-after-free via malformed project file).

1. Reconnaissance / Target Identification: An attacker identifies an ICS/OT environment using Omron CX-Position (part of the CX-One software suite) for programming or configuring Omron PLCs (e.g., CJ1, CS1, CP1 series). Target discovery may occur via LinkedIn profiling of engineering personnel, Shodan exposure of engineering workstations (rare), ICS asset inventory leaks, or direct social engineering within a supply-chain context. Engineering workstations are high-value targets because they hold credentials, network routes to PLCs, and often have local admin rights.

2. Triggering the Flaw: The attacker crafts a malicious .CPB or .CXT project file (or a packaged project containing the malformed CX-Position data). The file contains a deliberately malformed section that triggers the premature free of an internal object during parsing. The attacker hosts this file on a spearphishing site, sends it as an email attachment, or — in a supply-chain attack — embeds it in a "helpful" configuration update or as a poisoned entry on a shared engineering FTP/share.

3. Payload / Execution Method (Vulnerability Class Level): In a canonical UAF exploit, the attacker employs heap feng shui — priming the heap with controlled allocations to ensure the freed region is reallocated with an object containing attacker-controlled data (e.g., a fake vtables or function pointer array). When the dangling pointer is dereferenced for a virtual method call or data write, execution is redirected to a ROP chain or shellcode that runs in the context of the CX-Position process (likely running with the user's privileges, which on engineering PCs is frequently an administrator account). The payload may then drop a persistence mechanism, load an ICS-specific implant, or modify PLC configuration files.

4. Post-Exploitation Impact: With arbitrary code execution on the engineering workstation, the attacker can:

   • Extract stored credentials for PLCs and database connections.
   • Manipulate project files to alter control logic for the next download to the PLC (delayed sabotage).
   • Move laterally to programming PCs and HMIs, and pivot to SCADA servers that aggregate PLC data.
   • Because Engineering workstations often have elevated privileges and broad network access to the OT subnet, the attacker could propagate inside the OT network, potentially gaining the ability to modify PLC logic or ladder programs — a precursor to physical-impact attacks (e.g., manipulating safety interlocks).

Impact Assessment

• CVSS Score: 7.8 (High). The vector suggests local attack complexity low, with high confidentiality, integrity, and availability impact on the workstation itself.
• Affected Systems: All installations of Omron CX-Position ≤ 2.5.3. The broader CX-One suite may share affected components; however, no official cross-product listing is provided beyond the core product.
• Business Impact: Engineering workstations in OT environments are crown jewels. A compromised engineering station can lead to:
  • Intellectual Property Theft: PLC programs and HMIs are proprietary logic; a loss could reveal process recipes, alarm setpoints, and control strategies.
  • Production Manipulation: Attackers could alter machine sequence, causing quality loss, equipment damage, or safety incidents.
  • Ransomware/Extortion: An attacker gaining code execution on engineering machines often leads to OT-wide encryption or lockout, as seen in real-world ICS ransomware incidents (e.g., NotPetya crippling engineering tools).
• Blast Radius: While the CVSS reflects only the local machine, the realistic blast radius expands to the entire OT segment the workstation belongs to — all PLCs the station connects to, and any HMIs or historian systems on the same routable subnet.
• Exploitability & Existing Threats: EPSS score of 0.01409 means low exploitation likelihood historically, but this is a classic "low probability, high impact" scenario. No CISA KEV inclusion — no evidence of active exploitation in the wild.

Detection Guidance

Sigma Rule

title: Omron CX-Position Use-After-Free Exploitation
id: 9c8f3a2e-19ad-4a7c-b301-2d6c4eafaa78
status: experimental
description: Detects anomalous processes spawning or crash-related events that may indicate use-after-free exploitation of Omron CX-Position.
author: Valtersit Threat Intel
date: 2024/01/15
logsource:
    category: process_creation
    product: windows
detection:
    selection_parent:
        ParentImage|endswith:
            - '\cx-position.exe'
            - '\CXP.exe'
            - '\cxposition.exe'
    selection_child:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
            - '\wscript.exe'
            - '\cscript.exe'
            - '\rundll32.exe'
    selection_crash:
        EventID: 1000  # or 1001 for application error in System log
    condition: (selection_parent and selection_child) or selection_crash
level: high
falsepositives:
    - Legitimate use of scripts from engineering tools for automation
    - CRC32 scanner: A mismatch in the cyclic redundancy check indicates data corruption or tampering during the attack file delivery.

YARA Rule

rule Omron_CX_Position_UAF_CVE_2022_26417 {
    meta:
        author = "Valtersit Threat Intel"
        description = "Detect crafted Omron CX-Position project files potentially exploiting CVE-2022-26417"
        date = "2024-01-15"
        severity = "high"
        cve = "CVE-2022-26417"
    strings:
        $file_header = "CXP" // Common CX-Position header (may vary)
        $uaf_string1 = "CXP_PROJECT" ascii wide
        $uaf_string2 = "ODS_OCCUPIED" ascii wide  // hypothetical marker; infer from crash dumps
        $uaf_string3 = "SET_OBJECT" ascii wide
        $obj_array = { 48 8B 05 ?? ?? ?? ?? 48 8B 48 20 }  // mov rax, [rip+x]; mov rcx, [rax+20h] (ptr deref pattern)
        $free_followed_by_use = { 48 83 79 ?? 00 74 ?? FF 51 ?? FF 51 ?? } // test dword ptr [rcx+x], 0; jz; call [rcx+x]; call [rcx+x] (suspicious UAF pattern)
    condition:
        uint16(0) == 0x4358 and // 'XC' little endian indication
        (1 of ($obj_array*) or all of ($uaf_string*) or $free_followed_by_use) and
        filesize < 20MB
}

Suricata IDS Rule

alert http any any -> $HOME_NET any (msg:"Omron CX-Position Malicious Project File Download (CVE-2022-26417)"; flow:established,to_client; content:"Content-Disposition"; nocase; content:"filename="; nocase; pcre:"/\.(?:cxp|cxt)$/Ui"; content:!"Content-Encoding"; threshold:type both, track by_src, count 1, seconds 60; classtype:attempted-user; sid:20222641701; rev:1;)

Note: Network-based detection is less effective since the exploit is file-based and local. This rule alerts on common extensions for the CX-Position project files being downloaded to an environment, as a preliminary indicator. For file-based detection, rely on YARA and EDR behavioral rules.

Elastic Detection

sequence by process.entity_id with maxspan=10s
  [process where event.type == "start" and
     (process.parent.name : ("cx-position.exe", "CXP.exe") or
      process.parent.name : ("CX-One.exe", "CX-Programmer.exe")) and
     (process.name : ("cmd.exe", "powershell.exe", "wscript.exe", "cscript.exe", "rundll32.exe"))]

Alternate (event-based): Detect abnormal application crashes with evidence of subsequent code execution:

sequence by host.name with maxspan=300s
  [any where event.code == "1000" and winlog.provider_name == "Application Error" and message : "*cx-position*"]
  [process where event.action == "start" and process.name : ("cmd.exe", "powershell.exe", "wscript.exe", "cscript.exe")]

Splunk SPL Query

index=windows sourcetype=WinEventLog:Application EventCode=1000
| rex field=Message "Faulting application name:\s+(?<app_name>[^\s]+)"
| where match(app_name, "(?i)cx-position|CXP")
| table _time, host, app_name, Message, EventCode
| append [ search index=windows sourcetype=WinEventLog:Security
    EventCode=4688
    | where match(New_Process_Name, "(?i)cmd.exe|powershell.exe|wscript.exe|cscript.exe|rundll32.exe")
    | where match(Parent_Process_Name, "(?i)cx-position|CXP")
    | table _time, host, Parent_Process_Name, New_Process_Name, EventCode ]
| sort _time

Alternatively, look for abnormally long-running cx-position.exe processes with outbound connections to suspicious IPs:

index=netflow OR index=syslog (src_ip=10.0.0.0/8 AND dest_ip NOT IN [10.0.0.0/8]) 
| join src_ip [ search index=windows sourcetype=WinEventLog:Security EventCode=4688 
    | search New_Process_Name="*cx-position*" | rex field=New_Process_Name "(?<proc_name>[^\\]+)$" | table proc_name, dest_ip ]

Wazuh OSSEC Rule

<group name="otics,">
    <rule id="325286" level="12">
        <if_sid>18100</if_sid>  <!-- Windows Application Event -->
        <match>cx-position|CXP</match>
        <regex>Faulting application name: (cx-position|CXP)\.exe</regex>
        <description>CVE-2022-26417: Omron CX-Position use-after-free detected - possible exploitation via malicious project file.</description>
        <group>ics_ransomware,</group>
    </rule>
    <rule id="325287" level="14">
        <if_sid>20226417</if_sid>  <!-- After crash detected -->
        <match>cmd.exe|powershell.exe|wscript.exe|cscript.exe|rundll32.exe</match>
        <description>Post-crash shell process spawned by CX-Position - indicates active exploitation of CVE-2022-26417.</description>
    </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 2/4 — Only one source (the CNA) claims a patch exists; it has not been independently verified to actually remediate the vulnerability. Treat the patch as provisional.

1. Immediate Mitigations

• Block File Delivery: If engineering files are shared via email/web, deploy email attachment filtering to strip .cxp, .cxt, and related project extensions from untrusted senders. Consider blocking large project file downloads from non-engineering domains.
• User Interaction Controls: Enforce the principle of least privilege on engineering workstations. Even with UAF exploitation, code execution at a non-admin user level reduces impact. Implement Application Control (e.g., Windows Defender Application Control) to restrict the processes that can execute from within C:\Program Files (x86)\Omron\.
• Network Segmentation: Place engineering workstations in a separate VLAN and ensure they cannot access the internet except through a proxy. This mitigates C2 communication if exploitation succeeds.
• Endpoint Monitoring: Deploy EDR with behavioral rules (e.g., Sigma/EQL above) to detect crash-then-spawn patterns.

2. Patch/Upgrade Steps

• Obtain v2.5.4: Users with a valid Omron service contract should use the Auto Update function within CX-One/CX-Position to fetch the update. For users without an active contract, contact Omron Technical Support or an Omron representative to arrange an update — stressing the security relevance of this fixed version and requesting it be made available to all customers.
• Validation: After upgrade, verify the binary version (Help → About) shows 2.5.4 or later. Independently test by opening known-good and previously-crafted suspicious project files to confirm no crash; if the update is not truly fixed, report back to the community.

3. Long-Term Hardening

• ICS Asset Inventory: Maintain a current inventory of all CX-Position installations and owners, including license/contract status.
• Supply Chain Trust Boundary: Require digital signatures on all project files before they are opened; implement a VBA-style macro security policy for automation projects, or move to template-based development where files are only accepted from a controlled repository.
• Vendor Engagement: File a formal request with Omron to publish the patch publicly through a CISA ICS advisory, given the paywalled patch model is contrary to ICS-CERT best practices.
• Incident Readiness: Develop a playbook for "engineering workstation compromise," including procedures for isolating the PC, preserving captures, and not resetting PLC settings until the vulnerability is remediated.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2022-26417
2. CISA ICS Advisories (search for Omron CX-Position or CVE-2022-26417): https://www.cisa.gov/news-events/ics-advisories
3. CWE-416 Use After Free: https://cwe.mitre.org/data/definitions/416.html
4. Omron CX-One Product Page (for Auto Update references): https://www.ia.omron.com/products/family/2782/
5. MITRE ATT&CK Technique T1203 – Exploitation for Client Execution: https://attack.mitre.org/techniques/T1203/

Known Threat Actor Campaigns: None publicly identified at the time of writing. No exploitation-in-the-wild evidence is documented; the vulnerability is not listed in CISA KEV. However, the ICS/OT sector has seen increasing interest from state-sponsored actors in engineering software (e.g., TRITON affecting Triconex, PIPEDREAM/INCONTROLLER tools targeting multiple OT vendors), and file-based vulnerabilities in engineering suites remain a privileged attack vector for manipulation-of-control and ransomware operations.