What is CVE-2021-47891?

CVE-2021-47891 is a critical-severity vulnerability in Unified Intents Ab Remote, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-01-23.

How severe is CVE-2021-47891?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Auth bypass in Unified Intents Ab Remote

CVE-2021-47891

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.

Vulnerability class: Broken Authentication

Published 2026-01-23 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (58.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.001

Affected products

Unified Intents Ab Remote — versions 3.9.0.2463

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

References

www.exploit-db.com/exploits/49587 (exploit)
www.unifiedremote.com/ (product)
www.unifiedremote.com/download (product)
www.vulncheck.com/advisories/unified-remote-remote-code-execution (third-party-advisory)

Frequently asked questions

What is CVE-2021-47891?: CVE-2021-47891 is a critical-severity vulnerability in Unified Intents Ab Remote, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-01-23.
How severe is CVE-2021-47891?: Critical severity. CVSS v3 base score is 9.8 out of 10.