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CVE-2018-20818: Openplcproject Openplc V2 Firmware: Buffer overflow
CVE-2018-20818 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists 2 affected products, including Openplcproject Openplc V2 Firmware. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.
Vulnerability description
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.
Severity breakdown
CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Unchanged. Impact stays within the vulnerable component.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.
Affected products
- Openplcproject Openplc V2 Firmware: all versions listed by NVD
- Openplcproject Openplc V3 Firmware: all versions listed by NVD