Is CVE-2021-47891 in the CISA KEV catalog?

No. CVE-2021-47891 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-47891?

CVE-2021-47891 has a CVSS v3 base score of 9.8 (CRITICAL).

What is the EPSS score for CVE-2021-47891?

CVE-2021-47891 has an EPSS score of 0.80% (52th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-47891

CRITICAL

9.8

CVSS v3

NVD

Description

Unified Remote 3.9.0.2463 contains a remote code execution vulnerability that allows attackers to send crafted network packets to execute arbitrary commands. Attackers can exploit the service by connecting to port 9512 and sending specially crafted packets to open a command prompt and download and execute malicious payloads.

CWE-306

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Exploit Intelligence

0.80%probability of exploitation in 30 days

52ndpercentile

Moderate risk: more likely to be exploited than 52% 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.