Stack-based Buffer OverflowWeakness · CWE-121

CVE-2026-12847

CRITICAL · 10.0 CVSS v3.1 Published 2026-06-24
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click 8 weeks old

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
GV-I/O Box 4E is a smart embedded device with 4 input and 4 relays output that can be controlled over Ethernet and RS-485. DVRSearch is a service running by default on the IOBox listening for UDP messages on port 10001. Any user on the network can send messages to this service and interact with it. Upon receiving a UDP message, the server reads at most 1460 bytes into a local buffer and a pointer to the buffer is stored in a global variable: #### Gateway field stack overflow The following code is vulnerable to a stack overflow that is attacker-controlled: v7 = strlen(g_network_config->gateway); memcpy(&reply_buf[216], g_network_config->gateway, v7);

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

Stack-based buffer overflow in DVRSearch service on UDP port 10001. The gateway configuration value is copied via memcpy into a fixed-size local buffer at offset 216 without any length validation, allowing an attacker to overwrite stack frames by sending a crafted UDP message with an oversized gateway string.

MitigationApply vendor firmware update when available; otherwise restrict network access to the device or disable the DVRSearch service if not required.

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
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/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 checks

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

  1. Verify UDP port 10001 is listening
    Run 'netstat -anu | grep 10001' or 'nmap -sU -p 10001 <target_ip>' to check if UDP port 10001 is open and listening on the device
    Affected if UDP port 10001 is open and accepting packets - this is the attack surface for the overflow
  2. Confirm DVRSearch service is running
    Check running processes or service status on the GV-I/O Box 4E for a process named DVRSearch, or query the device SNMP/monitoring interface if available
    Affected if The DVRSearch service is active - this is the vulnerable component containing the overflow
  3. Assess network accessibility of the service
    Determine if UDP port 10001 is reachable from untrusted networks by checking firewall rules, ACLs, or performing a port scan from an external source
    Affected if The port is reachable from networks where untrusted attackers exist - exploitation requires network access to UDP port 10001
  4. Check device firmware version
    Access the device admin interface or check system information to identify the installed firmware version
    Affected if The installed firmware version has not been patched (compare against any vendor-released versions that address this vulnerability)

If the DVRSearch service on UDP port 10001 is exposed and accessible on the network, the GV-I/O Box 4E is vulnerable to remote code execution via the unbounded memcpy() overflow.

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 update when available; otherwise restrict network access to the device or disable the DVRSearch service if not required.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,600
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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-2026-12847 in production — separate from our analysis above.

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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
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