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RendezvousApplication · Tibco

CVE-2021-28817

HIGH · 7.8 CVSS v3.1 Published 2021-03-23
Fix available
A fix is available. Upgrade to after 8.5.1 or later.
See remediation →
80/100
Remediation priority · High
Zero-click

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 · unedited
The Windows Installation component of TIBCO Software Inc.'s TIBCO Rendezvous and TIBCO Rendezvous Developer Edition contains a vulnerability that theoretically allows a low privileged attacker with local access on some versions of the Windows operating system to insert malicious software. The affected component can be abused to execute the malicious software inserted by the attacker with the elevated privileges of the component. This vulnerability results from a lack of access restrictions on certain files and/or folders in the installation. Affected releases are TIBCO Software Inc.'s TIBCO Rendezvous: versions 8.5.1 and below and TIBCO Rendezvous Developer Edition: versions 8.5.1 and below.

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 confidence

This is a local privilege escalation vulnerability in the Windows installer for TIBCO Rendezvous. The installer creates files/folders with overly permissive access controls, allowing a low-privileged local attacker to replace or modify executables in the installation directory. When the installer or its components run, they execute the attacker's malicious code with elevated (SYSTEM or administrator) privileges.

MitigationApply the vendor patch by upgrading TIBCO Rendezvous and TIBCO Rendezvous Developer Edition to version 8.5.1 or later. Until patched, restrict physical/local access to the server, monitor installation directories for unauthorized file modifications, and ensure users lack write access to TIBCO program directories.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
RendezvousApplication
Affected:<= 8.5.1

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
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify TIBCO Rendezvous installation path
    Check the Windows registry under HKLM\SOFTWARE\TIBCO\Rendezvous for the InstallPath value, or look in common locations like C:\Program Files\TIBCO\Rendezvous or C:\Program Files (x86)\TIBCO\Rendezvous
    Affected if TIBCO Rendezvous is installed and the installation path is found on the system
  2. Determine installed Tibco Rendezvous version
    Check the version of the rv.exe or tibrvjms.dll file in the installation directory by right-clicking the file, selecting Properties, and viewing the Details tab, or use PowerShell: Get-Item 'C:\Program Files\TIBCO\Rendezvous\rv.exe' | Select-Object VersionInfo
    Affected if The installed version is 8.5.1 or any version lower than 8.5.1
  3. Verify permissions on installation directory
    Right-click the TIBCO Rendezvous installation folder, select Properties, go to the Security tab, and examine the permissions for Users or authenticated users group. Alternatively, run: icacls 'C:\Program Files\TIBCO\Rendezvous'
    Affected if Users or authenticated users have Write or Modify permissions to the installation directory
  4. Check for weak permissions on executable files
    Run: icacls 'C:\Program Files\TIBCO\Rendezvous\*' | findstr /i "(Users|Everyone) (F|M|W)" to list executables with overly permissive access
    Affected if Executable files in the Rendezvous directory grant Write or Full Control to non-privileged users like Users group

A system is affected if TIBCO Rendezvous version 8.5.1 or lower is installed AND non-administrative users have write access to the installation directory or its executable files.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Upgrade available Upgrade to a release after 8.5.1
Interim mitigation

Apply the vendor patch by upgrading TIBCO Rendezvous and TIBCO Rendezvous Developer Edition to version 8.5.1 or later. Until patched, restrict physical/local access to the server, monitor installation directories for unauthorized file modifications, and ensure users lack write access to TIBCO program directories.

Fix this in Rendezvous Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-28817 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • 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