PHP File Inclusion (RFI/LFI)Weakness · CWE-98

CVE-2026-22503

HIGH · 8.1 CVSS v3.1 Published 2026-03-25
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
90/100
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
Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in ThemeREX Nelson nelson allows PHP Local File Inclusion.This issue affects Nelson: from n/a through <= 1.2.0.

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

ThemeREX Nelson WordPress theme <= 1.2.0 contains a PHP Local File Inclusion (LFI) vulnerability where the application improperly controls filenames used in include/require statements. This allows authenticated or unauthenticated attackers to include arbitrary PHP files from the local server, potentially leading to remote code execution if they can write malicious files or access sensitive system files.

MitigationUpdate ThemeREX Nelson to the latest patched version immediately. If no update is available, remove the theme or implement WAF rules to block directory traversal patterns in requests. Audit the codebase for unsafe use of include/require with user-controlled input.

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
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:H/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 ThemeREX Nelson theme is installed
    Navigate to wp-content/themes/ in your WordPress installation directory and check for a folder named 'nelson' or 'theme-rex-nelson'. Alternatively, in WordPress admin go to Appearance > Themes to list installed themes.
    Affected if The ThemeREX Nelson theme folder exists in the themes directory.
  2. Determine the installed theme version
    Open the style.css file within the nelson theme folder and look for the 'Version:' header in the file comments, or check the theme's main PHP file for a version constant.
    Affected if The version number found is 1.2.0 or lower.
  3. Identify vulnerable include/require patterns in theme files
    Search all PHP files in the nelson theme folder for code that uses include, require, include_once, or require_once with variables derived from request parameters (such as $_GET, $_POST, or $_REQUEST) without proper sanitization. Common patterns include 'include($_GET["file"])' or 'require($theme_dir . $_POST["template"])'.
    Affected if Any PHP file in the theme contains include/require statements using unsanitized user input in the file path.
  4. Check for directory traversal in theme routing
    Examine the theme's index.php or any routing files for code that processes page templates or components based on URL parameters. Look for patterns where a parameter value is directly appended to a path and used in include/require.
    Affected if The theme routes requests through parameters that are used in include/require statements without validation.

Your environment is affected if the ThemeREX Nelson theme version is 1.2.0 or lower AND the theme contains code that uses include/require with unsanitized user-controlled input for file paths.

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

Update ThemeREX Nelson to the latest patched version immediately. If no update is available, remove the theme or implement WAF rules to block directory traversal patterns in requests. Audit the codebase for unsafe use of include/require with user-controlled input.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
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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-2026-22503 in production — separate from our analysis above.

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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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