Traveler For Microsoft OutlookApplication · Hcltech

CVE-2024-42191

CRITICAL · 9.8 CVSS v3.1 Published 2025-05-30
Fix available
A fix is available. Upgrade to 3.0.12 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges 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
HCL Traveler for Microsoft Outlook (HTMO) is susceptible to a COM hijacking vulnerability which could allow an attacker to modify or replace the application with malicious content.

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

HCL Traveler for Microsoft Outlook (HTMO) contains a COM hijacking vulnerability where attackers can manipulate Windows COM registry entries to redirect legitimate application components to malicious code, allowing modification or replacement of the application with malicious content.

MitigationApply the vendor-supplied patch from HCL when available; in the interim, restrict write access to COM-related registry keys and monitor for unauthorized modifications to HTMO application components.

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
Traveler For Microsoft OutlookApplication
Affected:< 3.0.12

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 checks

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

  1. Check if HCL Traveler for Microsoft Outlook is installed
    Open Windows Control Panel > Programs and Features, or run 'Get-ItemProperty HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\* | Where-Object {$_.DisplayName -like "*HCL Traveler*"}' in PowerShell to find HTMO installation entries
    Affected if HTMO is listed in installed programs or registry with a version below 3.0.12
  2. Verify HTMO version number
    Check the installed version from Program Files\HCL\Traveler For Microsoft Outlook folder, or use 'Get-ItemProperty' on the installation registry key to read the Version or DisplayVersion value
    Affected if Installed version is lower than 3.0.12 or version cannot be determined
  3. Inspect COM registry keys for HTMO CLSIDs
    Open Registry Editor and navigate to HKCR\CLSID\ for entries containing 'HCL' or 'Traveler' in the ProgID, or run 'Get-ChildItem HKCR:\CLSID -Recurse | Where-Object {$_.GetValue('') -like "*HCL*" -or $_.GetValue('') -like "*Traveler*"}' to list HTMO-related COM registrations
    Affected if COM entries exist pointing to non-standard or missing DLL paths, or CLSIDs reference unexpected file locations outside the HTMO installation directory
  4. Check COM DLL hijacking opportunities
    Examine the InprocServer32 entries under HTMO CLSIDs in HKCR\CLSID\{CLSID}\InprocServer32 to verify DLL paths are legitimate, looking for DLLs loaded from user-writable directories or unexpected paths
    Affected if Any InprocServer32 DLL path is located outside the official HTMO Program Files directory or points to a DLL that does not exist
  5. Review permissions on COM registry keys
    Use 'Get-Acl HKCR:\CLSID\* -ErrorAction SilentlyContinue | Where-Object {$_.AccessToString -like "*Users*" -and $_.AccessToString -like "*Write*"}' to identify CLSID keys with weak permissions, or manually check registry key permissions via regedit
    Affected if Non-administrator users have Write or FullControl permissions on HTMO-related COM registry keys, allowing potential modification

A user is affected if HCL Traveler for Microsoft Outlook is installed with a version below 3.0.12 and any COM registry entries show unexpected DLL paths or overly permissive access controls.

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.

dbcve · scoped
Upgrade available Upgrade to 3.0.12 or later
Fixed in 3.0.12
Interim mitigation

Apply the vendor-supplied patch from HCL when available; in the interim, restrict write access to COM-related registry keys and monitor for unauthorized modifications to HTMO application components.

Recommended fix Moderate confidence

3.0.12

  1. Check the current installed version of HCL Traveler for Microsoft Outlook (HTMO) by opening the application and navigating to Help > About, or checking in Windows Programs and Features
  2. Access the HCL Software support portal at support.hcl-software.com and navigate to the HCL Traveler for Microsoft Outlook downloads section
  3. Download HCL Traveler for Microsoft Outlook version 3.0.12 or later
  4. Before upgrading, backup the existing HTMO configuration, data files, and any custom settings
  5. Close HCL Traveler for Microsoft Outlook and any related services
  6. Run the downloaded installer for version 3.0.12 or later as an administrator
  7. Follow the on-screen installation prompts to complete the upgrade
  8. After installation, verify the new version by checking Help > About in the application

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Traveler For Microsoft Outlook Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
Get the upgrade done

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

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dbcve dependency scanner

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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-2024-42191 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