Improper Input ValidationWeakness · CWE-20

CVE-2026-9157

HIGH · 8.4 CVSS v3.1 Published 2026-05-21
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
89/100
Remediation priority · High
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
Improper input validation, Unrestricted upload of file with dangerous type vulnerability in Gmission Web Fax allows Remote Code Inclusion. This issue affects Web Fax: from 3.0 before 3.1.

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 · moderate confidence

Gmission Web Fax version 3.0 contains an unrestricted file upload vulnerability due to improper input validation, allowing attackers to upload files with dangerous types (e.g., executable scripts). When these malicious files are subsequently accessed or included by the web application, they enable Remote Code Inclusion (RCI), permitting arbitrary code execution on the server.

MitigationUpgrade to Gmission Web Fax version 3.1 or later. Additionally, implement strict allowlist-based file type validation, store uploads outside the webroot, and disable script execution in upload directories.

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

CVSS:3.1/AV:L/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. Identify Gmission Web Fax installation
    Search for Gmission Web Fax files in the web server document root, application directories, or installed packages. Common locations: /var/www/html/, /opt/, or check the application inventory.
    Affected if Gmission Web Fax is installed and running in the environment
  2. Determine installed version
    Locate the version file, About page, or check the application binaries. Common paths: version.php, info.php, or the main executable. Compare the version number to the affected range (before 3.1).
    Affected if The installed version is 3.0 or any version lower than 3.1
  3. Confirm Web Fax upload feature is enabled
    Access the Web Fax application interface and navigate to the upload functionality. Check if the upload form/module is accessible and not disabled in the application settings or web server configuration.
    Affected if The upload feature is active and accessible to users
  4. Inspect file upload configuration
    Review the file upload handler configuration, typically in the web application's config files, php.ini, or web server settings. Look for settings that control allowed file extensions and MIME types.
    Affected if No server-side validation exists or dangerous file types (such as .php, .exe, .js) are permitted for upload

The environment is affected if Gmission Web Fax version 3.0 or lower is installed with the upload feature enabled and without proper server-side file type restrictions.

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

Upgrade to Gmission Web Fax version 3.1 or later. Additionally, implement strict allowlist-based file type validation, store uploads outside the webroot, and disable script execution in upload directories.

Recommended fix Moderate confidence

Gmission Web Fax version 3.1

  1. Verify current Gmission Web Fax version is 3.0 by checking the application's version information or admin interface
  2. Obtain the version 3.1 release package from the official vendor (Gmission) at www.gmission.co.kr
  3. Review release notes for version 3.1 to understand changes and any prerequisites
  4. Create a full backup of the current system including application files and database
  5. Test the upgrade in a non-production environment first
  6. Apply the version 3.1 upgrade following vendor-provided installation instructions
  7. Verify the upgrade was successful by checking the new version number
  8. Test that the Web Fax functionality works correctly post-upgrade
Caveat No specific breaking changes documented for this minor version upgrade; standard upgrade precautions apply

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

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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Scan for this in your stack

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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-2026-9157 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
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  • Version or environment caveats, and links to real fixes
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