CVE-2021-30187
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 · uneditedCODESYS V2 runtime system SP before 2.4.7.55 has Improper Neutralization of Special Elements used in an OS Command.
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 confidenceCODESYS V2 runtime system versions Service Pack before 2.4.7.55 are vulnerable to improper neutralization of special elements in OS commands, allowing command injection. This is a classic CWE-78 (OS Command Injection) vulnerability where user-supplied input is not properly sanitized before being passed to system command execution.
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< fw08< fw08< fw08< fw15< fw15< fw15< fw15< fw16CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
CVSS:3.1/AV:L/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify the Wago 750 series model numberLocate the device labeling on the PLC hardware or query the device system information to confirm the exact model (e.g., 750-880, 750-881, 750-882, 750-885, 750-889, 750-890, 750-891, or 750-893)Affected if The model is one of the eight affected variants listed in the CVE
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Determine the installed firmware versionAccess the PLC web interface, use the Wago toolchain, or query the device via its management interface to retrieve the current firmware version numberAffected if The firmware version is below the threshold: < fw08 for models 893/891/890, < fw15 for models 889/885/882/881, or < fw16 for model 880
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Confirm CODESYS V2 runtime is activeCheck if the CODESYS V2 runtime system is running on the PLC, typically via the runtime status page or by querying the service/process list on the deviceAffected if CODESYS V2 runtime is enabled and actively running on the affected device
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Verify the web management interface is accessibleDetermine if the PLC web interface (Wago Web-Based Management) is enabled and reachable on the networkAffected if The web interface is exposed, as this is the attack vector for the command injection vulnerability
The environment is affected if it is a Wago 750 series PLC (880/881/882/885/889/890/891/893) with firmware version below the specified threshold and the CODESYS V2 runtime with web interface is active.
Generated from the published advisory. Verify against your own configuration.
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 dataUpdate CODESYS V2 runtime system to version 2.4.7.55 or later. In ICS/OT environments, validate the update in a staging environment before production deployment to ensure process continuity.
- Consultation4.0 h
- Implementation4.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,504.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30187 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-30187 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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
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