CVE-2018-20818
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and...
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and OpenPLC_v3 versions. It occurs in the modbus.cpp mapUnusedIO() function, which can cause a runtime crash of the PLC or possibly have unspecified other impact.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and OpenPLC_v3 versions. It occurs in the modbus.cpp mapUnusedIO() function, which can cause a runtime crash of the PLC or possibly have unspecified other impact.
- Record
CVE-2018-20818- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-119
- Updated
- 2026-11-02
CVE List No score
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and OpenPLC_v3 versions. It occurs in the modbus.cpp mapUnusedIO() function, which can cause a runtime crash of the PLC or possibly have unspecified other impact.
- Record
CVE-2018-20818- Updated
- 2026-11-02
EUVDEUVD-2018-13360 No score
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and OpenPLC_v3 versions. It occurs in the modbus.cpp mapUnusedIO() function, which can cause a runtime crash of the PLC or possibly have unspecified other impact.
- Record
EUVD-2018-13360- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-j22f-7hvx-mqp8
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and...
A buffer overflow vulnerability was discovered in the OpenPLC controller, in the OpenPLC_v2 and OpenPLC_v3 versions. It occurs in the modbus.cpp mapUnusedIO() function, which can cause a runtime crash of the PLC or possibly have unspecified other impact.
- Record
GHSA-j22f-7hvx-mqp8- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-119
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-20818 is a critical vulnerability (CVSS 9.8) in Openplcproject Openplc V2 Firmware, published April 21, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.53%, the 74th percentile. No source names a fixed version.