CVE-2021-47770

Severity CVSS v4.0:

HIGH

Type:

CWE-94 Code Injection

Publication date:

21/01/2026

Last modified:

21/01/2026

Description

OpenPLC v3 contains an authenticated remote code execution vulnerability that allows attackers with valid credentials to inject malicious code through the hardware configuration interface. Attackers can upload a custom hardware layer with embedded reverse shell code that establishes a network connection to a specified IP and port, enabling remote command execution.

Impact

Vector 4.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N CVSS v4.0 Severity and Metrics:

Base Score: 8.60 HIGH
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): High
User Interaction (UI): None
Confidentiality (VC): High
Integrity (VI): High
Availability (VA): High
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None

Base Score 4.0

8.60

Severity 4.0

HIGH

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.80 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

8.80

Severity 3.x

HIGH

CVE-2021-47770

Description

Impact

References to Advisories, Solutions, and Tools