CVE-2021-47891
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedUnified 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceUnified Remote 3.9.0.2463 has a critical RCE vulnerability where attackers send specially crafted network packets to port 9512, allowing them to open a command prompt and download/execute arbitrary malicious payloads.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Confirm Unified Remote is installedCheck installed programs or running processes for 'Unified Remote' or 'unifiedremote' entryAffected if Unified Remote software is present on the system
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Identify the installed versionUse the application's built-in about or help function, check Add/Remove Programs, or query the installed package information to determine the exact version numberAffected if The version is 3.9.0.2463 or earlier (no fixed version specified, so treat this specific build as affected)
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Verify the network service is active on port 9512Run 'netstat -an | findstr 9512' or 'ss -tlnp | grep 9512' to check if the application is listening on port 9512Affected if Port 9512 is in LISTEN state and bound to a network interface accessible externally
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Check if the server accepts remote connections without authenticationObserve whether the service binds to 0.0.0.0:9512 or all interfaces rather than localhost only, using 'netstat -an' outputAffected if The service listens on 0.0.0.0 or a non-loopback address, allowing external network access
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Assess network exposure of port 9512Review firewall rules, router configurations, or use a port scanner from an external host to determine if port 9512 is reachable from untrusted networksAffected if Port 9512 is accessible from outside the local network or from untrusted systems
A system is affected if Unified Remote version 3.9.0.2463 or earlier is installed and the port 9512 service is accessible from the network.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataImmediately upgrade to a patched version of Unified Remote. If patching is not immediately possible, block port 9512 at the firewall or disable the service until the patch can be applied.
- Consultation2.0 h
- Implementation3.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-47891 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-47891 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data