Missing AuthenticationWeakness · CWE-306

CVE-2026-23751

CRITICAL · 9.8 CVSS v3.1 Published 2026-04-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
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
Kofax Capture, now referred to as Tungsten Capture, version 6.0.0.0 (other versions may be affected) exposes a deprecated .NET Remoting HTTP channel on port 2424 via the Ascent Capture Service that is accessible without authentication and uses a default, publicly known endpoint identifier. An unauthenticated remote attacker can exploit .NET Remoting object unmarshalling techniques to instantiate a remote System.Net.WebClient object and read arbitrary files from the server filesystem, write attacker-controlled files to the server, or coerce NTLMv2 authentication to an attacker-controlled host, enabling sensitive credential disclosure, denial of service, remote code execution, or lateral movement depending on service account privileges and network environment.

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

Kofax Capture (Tungsten Capture) version 6.0.0.0 exposes a deprecated, unauthenticated .NET Remoting HTTP channel on port 2424 via the Ascent Capture Service. The service uses a default, publicly known endpoint identifier, allowing unauthenticated remote attackers to exploit .NET Remoting object unmarshalling to read/write arbitrary files, coerce NTLMv2 authentication, and achieve remote code execution or lateral movement depending on service account privileges.

MitigationImmediately block port 2424 at the network perimeter or disable the Ascent Capture Service if not required; network segmentation can limit exposure while a vendor patch is developed and tested.

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 checks

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

  1. Confirm Kofax Capture installation
    Check for Kofax Capture or Tungsten Capture in installed programs (Programs and Features), or look for installation directories such as C:\Program Files\Kofax\ or C:\Program Files\Tungsten\Capture\. Check Windows Registry under HKLM\SOFTWARE\Kofax or HKLM\SOFTWARE\Tungten for Capture entries.
    Affected if Kofax Capture or Tungsten Capture is installed
  2. Verify installed version is 6.0.0.0
    Locate the version information in the installation directory (often in an About or version file), or check the product version in Programs and Features. Compare the exact version string to 6.0.0.0.
    Affected if Installed version is exactly 6.0.0.0 (no other versions are affected per this CVE)
  3. Confirm Ascent Capture Service is running
    Open Services (services.msc) and look for a service named 'Ascent Capture Service' or 'Kofax Capture Service'. Alternatively, run 'sc query' or 'Get-Service' PowerShell command to enumerate running services.
    Affected if The Ascent Capture Service is present and running
  4. Check if port 2424 is listening
    Run 'netstat -an | findstr :2424' or 'Get-NetTCPConnection -LocalPort 2424' to check if port 2424 is open and bound to a listening service. This port is used by the .NET Remoting HTTP channel.
    Affected if Port 2424 is listening/open on any network interface (0.0.0.0 or specific IP)
  5. Verify .NET Remoting endpoint accessibility
    Attempt a basic HTTP request to http://localhost:2424/AscentCapture or use a tool like nmap to probe the endpoint: nmap -p 2424 --script http-title <target> or curl http://<target>:2424/. The service uses a default, publicly known endpoint identifier.
    Affected if HTTP response is received from port 2424 indicating .NET Remoting service is accessible

A system is affected if Kofax Capture version 6.0.0.0 is installed with the Ascent Capture Service running and port 2424 open/exposed, allowing unauthenticated .NET Remoting access.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Immediately block port 2424 at the network perimeter or disable the Ascent Capture Service if not required; network segmentation can limit exposure while a vendor patch is developed and tested.

Have this fixed Scoped from the published advisory
  • Consultation8.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA4.0 h
30.0 hours of engineering $5,380
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Scan for this in your stack

Free · runs locally
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-2026-23751 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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