Missing AuthenticationWeakness · CWE-306

CVE-2026-0647

HIGH · 8.8 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 →
97/100
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
An improper authentication security issue exists within the 1794-AENTR adapter's embedded web server. The vulnerability allows an unauthenticated attacker to change the device's web interface password by sending a crafted HTTP GET request to a specific endpoint, without any prior authentication being required. If exploited, this could lead to unauthorized access, account takeover, and loss of the device’s embedded web server’s availability.

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 · high confidence

This is an improper authentication vulnerability in the 1794-AENTR adapter's embedded web server. An unauthenticated attacker can change the device's web interface password by sending a crafted HTTP GET request to a specific endpoint, leading to account takeover and denial of service.

MitigationRestrict network access to the device's web interface via firewall rules or VLAN segmentation. If available, apply vendor firmware updates to remediate the authentication bypass.

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:L/VI:H/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. Identify 1794-AENTR adapter on the network
    Scan the network for devices with the 1794-AENTR model identifier, or check network documentation for Flex I/O Ethernet adapters. Use Nmap or network scanning tools to detect devices responding to Ethernet/IP queries.
    Affected if The 1794-AENTR adapter is present in the environment.
  2. Verify embedded web server is enabled
    Access the device's web interface via its IP address using a browser, or query the device configuration via EtherNet/IP to check if the embedded web server feature is active. Look for HTTP/HTTPS ports (typically 80/443) responding on the device's IP.
    Affected if The embedded web server is enabled and responding to HTTP/HTTPS requests.
  3. Check network exposure of the web interface
    Determine if the device's web server IP port is accessible from untrusted networks. Review firewall rules, VLAN assignments, and network segmentation to verify whether the web interface is reachable from outside the control network.
    Affected if The web interface is accessible from networks outside the trusted control system zone.
  4. Confirm web interface accepts unauthenticated requests
    Send a crafted HTTP GET request to the device and observe if the response indicates authentication is bypassed or if password change parameters are accepted without prior authentication. Compare behavior against expected authentication challenges.
    Affected if The web interface accepts requests and responds without requiring valid authentication credentials.

A user is affected if a 1794-AENTR adapter with its embedded web server enabled is present and the web interface is accessible from the network without authentication barriers.

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

Restrict network access to the device's web interface via firewall rules or VLAN segmentation. If available, apply vendor firmware updates to remediate the authentication bypass.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
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Scan for this in your stack

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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-2026-0647 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
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