1766 L32awaHardware / appliance · Rockwellautomation

CVE-2016-5645

HIGH · 7.3 CVSS v3.1 Published 2016-08-24
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
82/100
Remediation priority · High
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
Rockwell Automation MicroLogix 1400 PLC 1766-L32BWA, 1766-L32AWA, 1766-L32BXB, 1766-L32BWAA, 1766-L32AWAA, and 1766-L32BXBA devices have a hardcoded SNMP community, which makes it easier for remote attackers to load arbitrary firmware updates by leveraging knowledge of this community.

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

The Rockwell Automation MicroLogix 1400 PLC models (1766-L32BWA, 1766-L32AWA, 1766-L32BXB, 1766-L32BWAA, 1766-L32AWAA, and 1766-L32BXBA) contain a hardcoded SNMP community string embedded in the firmware. This static credential allows remote attackers who discover the community string to authenticate to the device's SNMP service and load arbitrary firmware updates, effectively allowing complete device compromise.

MitigationContact Rockwell Automation for a firmware update that removes or allows changing the hardcoded SNMP community string. In the interim, isolate affected devices on a restricted network segment with SNMP access blocked from untrusted networks.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
1766 L32awaHardware / appliance
Affected:all versions
1766 L32awaaHardware / appliance
Affected:all versions
1766 L32bwaHardware / appliance
Affected:all versions
1766 L32bwaaHardware / appliance
Affected:all versions
1766 L32bxbHardware / appliance
Affected:all versions
1766 L32bxbaHardware / appliance
Affected:all versions

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
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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 the PLC model
    Access the PLC through RSLogix/Rockwell software or physical label and confirm the exact model number matches 1766-L32BWA, 1766-L32AWA, 1766-L32BXB, 1766-L32BWAA, 1766-L32AWAA, or 1766-L32BXBA
    Affected if Device model is one of the six listed models (all versions are affected)
  2. Verify SNMP service status
    Check if SNMP is enabled on the device via the PLC configuration or by scanning UDP port 161 on the device IP address
    Affected if SNMP is enabled and responding on the device
  3. Assess network exposure of SNMP port
    Scan the network to determine if UDP port 161 is accessible from untrusted network segments or the internet
    Affected if SNMP port 161 is exposed to untrusted networks or directly accessible from outside the local control system network
  4. Test for hardcoded SNMP community string
    If SNMP is enabled and accessible, attempt an SNMP query using known default or publicly disclosed community strings for this device (the hardcoded string is embedded in firmware)
    Affected if SNMP authentication succeeds with a hardcoded community string, indicating the vulnerability is exploitable

If the device is a MicroLogix 1400 model from the affected list and SNMP is enabled and accessible, the hardcoded community string vulnerability is present and exploitable.

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

Contact Rockwell Automation for a firmware update that removes or allows changing the hardcoded SNMP community string. In the interim, isolate affected devices on a restricted network segment with SNMP access blocked from untrusted networks.

Fix this in 1766 L32awa Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing10.0 h
  • Review / QA4.0 h
32.0 hours of engineering $5,580
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Scan for this in your stack

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dbcve dependency scanner

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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-2016-5645 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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