dbcve.org
Memory LeakWeakness · CWE-401

CVE-2026-0646

HIGH · 8.7 CVSS v4.0 Published 2026-06-16
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
96/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A denial-of-service security issue exists within the 1794-AENTR adapter due to improper memory handling of CIP protocol requests. This vulnerability can result in the adapter faulting and losing connection to its associated I/O modules, requiring a manual reset to recover.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

The 1794-AENTR adapter has a denial-of-service vulnerability caused by improper memory handling when processing CIP protocol requests. This causes the adapter to fault and lose communication with connected I/O modules, requiring manual reset for recovery.

MitigationApply vendor firmware updates when available, implement network segmentation to isolate industrial control devices, and consider rate limiting or filtering CIP protocol traffic as a compensating control.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm device model
    Identify the 1794-AENTR EtherNet/IP adapter in your environment. Check the device nameplate, network configuration, or management interface to verify the exact model number matches '1794-AENTR'.
    Affected if The device model is confirmed as 1794-AENTR and is present on your network.
  2. Check firmware version
    Access the device web interface, Rockwell Automation Studio 5000, or RSLinx Classic. Navigate to the device properties or firmware revision field to retrieve the installed firmware version.
    Affected if The installed firmware version falls within the vulnerable version range for this CVE (compare your version to vendor release notes for patch status).
  3. Verify network accessibility
    Ping the IP address assigned to the 1794-AENTR adapter or attempt a TCP connection to port 44818 (EtherNet/IP) using a network diagnostic tool. Confirm the device responds to network requests.
    Affected if The device is network-reachable, meaning an external attacker could send malicious CIP packets to it.
  4. Check CIP protocol exposure
    Verify that the adapter has CIP messaging enabled and is configured to process CIP requests from network sources. Review the adapter's communication settings in RSLogix/Studio 5000 or the web-based configuration interface.
    Affected if CIP protocol processing is enabled and the adapter accepts CIP requests from the network, exposing the memory handling flaw.
  5. Inspect for fault indicators
    Query the device status via RSLinx, Studio 5000, or the web interface. Look for faulted state indicators, communication loss messages, or Module Fault status. Review system logs for recent unexpected disconnects from I/O modules.
    Affected if The adapter is currently in a faulted state or has recently lost connection to associated I/O modules without an authorized cause.

You are affected if you have a 1794-AENTR adapter with a firmware version within the vulnerable range, CIP protocol is enabled, and the device is network-accessible to potential attackers.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply vendor firmware updates when available, implement network segmentation to isolate industrial control devices, and consider rate limiting or filtering CIP protocol traffic as a compensating control.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-0646 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data