dbcve.org
Path TraversalWeakness · CWE-22

CVE-2026-4350

HIGH · 8.1 CVSS v3.1 Published 2026-04-03
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
87/100
Remediation priority · High
Remotely reachable 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 Perfmatters plugin for WordPress is vulnerable to arbitrary file deletion via path traversal in all versions up to, and including, 2.5.9.1. This is due to the `PMCS::action_handler()` method processing the `$_GET['delete']` parameter without any sanitization, authorization check, or nonce verification. The unsanitized filename is concatenated with the storage directory path and passed to `unlink()`. This makes it possible for authenticated attackers, with Subscriber-level access and above, to delete arbitrary files on the server by using `../` path traversal sequences, including `wp-config.php` which would force WordPress into the installation wizard and allow full site takeover.

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

The Perfmatters WordPress plugin versions up to 2.5.9.1 contain an arbitrary file deletion vulnerability in the PMCS::action_handler() method. The method processes the $_GET['delete'] parameter without any sanitization, authorization check, or nonce verification, then concatenates the unsanitized filename with the storage directory path and passes it to PHP's unlink() function. This allows authenticated attackers with Subscriber-level access to use '../' path traversal sequences to delete arbitrary files on the server.

MitigationUpdate Perfmatters to version 2.5.10 or later which includes proper path sanitization and authorization checks. Until the update is applied, consider disabling the plugin or implementing web application firewall rules to block requests with path traversal sequences to the affected endpoint.

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

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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. Verify Perfmatters plugin is installed
    In WordPress admin, go to Plugins > Installed Plugins and look for Perfmatters in the list. Alternatively, check if the /wp-content/plugins/perfmatters/ directory exists on the server.
    Affected if Perfmatters plugin is installed and active
  2. Determine installed Perfmatters version
    In the WordPress Plugins admin page, locate Perfmatters and read the version number displayed beneath the plugin name. Alternatively, inspect the plugin header in /wp-content/plugins/perfmatters/plugin.php or readme.txt for the Version field.
    Affected if The installed version is earlier than 2.5.9.2
  3. Confirm user registration is enabled
    In WordPress admin, navigate to Settings > General and locate the Membership section. Check if the option 'Anyone can register' is ticked.
    Affected if Anyone can register is enabled on the site
  4. Check for existing subscriber-level accounts
    In WordPress admin, go to Users and use the role filter to display only Subscribers, or query the wp_usermeta table for users with wp_capabilities containing 'subscriber'.
    Affected if Any user accounts with Subscriber role exist in the system

You are affected if Perfmatters is installed with a version earlier than 2.5.9.2 AND user registration is enabled OR any subscriber-level user accounts exist on the site.

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

Update Perfmatters to version 2.5.10 or later which includes proper path sanitization and authorization checks. Until the update is applied, consider disabling the plugin or implementing web application firewall rules to block requests with path traversal sequences to the affected endpoint.

Recommended fix Moderate confidence

Version higher than 2.5.9.1 (check official Perfmatters channels for exact fixed release)

  1. Navigate to the WordPress admin dashboard
  2. Go to Plugins > Installed Plugins
  3. Locate Perfmatters plugin
  4. Check the current version number installed
  5. Visit the official Perfmatters website (perfmatters.io) or WordPress plugin repository to verify the latest stable version
  6. If the installed version is lower than the fixed release, click 'Update Now' to upgrade the plugin
  7. Alternatively, you can manually download the fixed version from the official source and upload it via Plugins > Add New > Upload Plugin
  8. After updating, verify the plugin is functioning correctly and test that the vulnerability is no longer present

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

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
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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-2026-4350 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