CVE-2024-50956
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 · uneditedA buffer overflow in the RecvSocketData function of Inovance HCPLC_AM401-CPU1608TPTN 21.38.0.0, HCPLC_AM402-CPU1608TPTN 41.38.0.0, and HCPLC_AM403-CPU1608TN 81.38.0.0 allows attackers to cause a Denial of Service (DoS) or execute arbitrary code via a crafted Modbus message.
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 confidenceBuffer overflow in the RecvSocketData function of Inovance HCPLC PLCs allows remote attackers to cause denial of service or execute arbitrary code via crafted Modbus messages. The vulnerability exists in the network communication handling code of three specific CPU module firmware versions.
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
- Adjacent
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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 PLC modelAccess the PLC's management interface or use discovery tools to confirm the device is an Inovance HCPLC PLC. Check the model number and confirm it belongs to the HCPLC series.Affected if The device is not an Inovance HCPLC PLC, then this CVE does not apply.
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Determine firmware versionAccess the PLC's web-based management interface, use the vendor's configuration software, or query the device via its management protocol to retrieve the current firmware version of the CPU module.Affected if The installed firmware version matches one of the three affected CPU module versions (compare against vendor's list of affected versions).
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Verify Modbus communication is enabledCheck the PLC configuration or network settings to confirm that Modbus/TCP communication is enabled on the device. This may be via the engineering software, web interface, or by observing Modbus port (502) listening status.Affected if Modbus communication is enabled and exposed on the network, making the device reachable to crafted Modbus messages.
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Assess network exposureReview network segmentation and firewall rules to determine if the PLC's Modbus port (502/TCP) is accessible from untrusted networks or directly from the internet.Affected if The PLC's Modbus interface is accessible from untrusted network segments, allowing remote attackers to send crafted messages.
You are affected if you have an Inovance HCPLC PLC with a CPU module firmware version matching one of the three affected versions, and Modbus communication is enabled and reachable from your network.
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 dataApply vendor firmware patches when available; meanwhile, network segment the affected PLCs and implement Modbus traffic monitoring to detect anomalous messages.
- Consultation12.0 h
- Implementation8.0 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 $9,216.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2024-50956 — 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-2024-50956 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
- No spam, self-promotion, credentials, or personal data