Is CVE-2021-47770 in the CISA KEV catalog?

No. CVE-2021-47770 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-47770?

CVE-2021-47770 has a CVSS v3 base score of 8.8 (HIGH).

What is the EPSS score for CVE-2021-47770?

CVE-2021-47770 has an EPSS score of 0.63% (46th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-47770

HIGH

8.8

CVSS v3

NVD

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.

CWE-94Code Injection

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Exploit Intelligence

0.63%probability of exploitation in 30 days

46thpercentile

Moderate risk: more likely to be exploited than 46% of all known CVEs.

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-01-26.