Path TraversalWeakness · CWE-22

CVE-2026-42756

CRITICAL · 9.9 CVSS v3.1 Published 2026-05-27
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 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 Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Ludwig You QuickWebP &#8211; Compress / Optimize Images &amp; Convert WebP | SEO Friendly quickwebp allows Path Traversal.This issue affects QuickWebP &#8211; Compress / Optimize Images &amp; Convert WebP | SEO Friendly: from n/a through <= 3.2.7.

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

A Path Traversal vulnerability in the QuickWebP WordPress plugin (versions <= 3.2.7) allows attackers to access files outside the intended restricted directory by manipulating file path inputs with '../' sequences. This improper limitation of pathname to a restricted directory enables unauthorized file system access.

MitigationImplement strict input validation and sanitization for all file path parameters, using allowlist validation and canonicalization to resolve paths before checking they fall within allowed directories. Replace direct file operations with WordPress built-in functions that handle path security.

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
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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. Locate the QuickWebP plugin installation
    Check the WordPress plugins directory at wp-content/plugins/ for a folder named 'quickwebp' or similar. Also check wp-admin/plugins.php in the WordPress admin panel for the plugin listing.
    Affected if The QuickWebP plugin folder exists in the WordPress plugins directory.
  2. Determine the installed version
    Open the main plugin file (typically quickwebp.php or similar in the plugin folder) and look for the version comment header (e.g., 'Version: 3.2.7'). Alternatively, check the WordPress plugin admin page which displays the version number.
    Affected if The installed version is 3.2.7 or any earlier version up to and including 3.2.7.
  3. Verify if the plugin is active
    In the WordPress admin, go to Plugins > Installed Plugins and check if QuickWebP shows as 'Active', or query the wp_options table for the option_name 'active_plugins' to see if quickwebp is listed.
    Affected if The QuickWebP plugin is currently active on the WordPress site.
  4. Inspect web server access logs for path traversal attempts
    Review web server access logs (Apache access.log, Nginx access.log) for requests to the QuickWebP plugin endpoints containing '../' sequences or absolute paths like '/etc/passwd', 'wp-config.php', or similar system file references. Search for patterns like '..%2F', '..\', or direct file path requests.
    Affected if Log entries show suspicious path traversal patterns targeting the QuickWebP plugin with '../' sequences or attempts to access system files outside the web root.

You are affected if the QuickWebP plugin versions 3.2.7 or earlier are installed and active on your WordPress site, especially if web server logs show path traversal attempts targeting the plugin.

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

Implement strict input validation and sanitization for all file path parameters, using allowlist validation and canonicalization to resolve paths before checking they fall within allowed directories. Replace direct file operations with WordPress built-in functions that handle path security.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-42756 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2026-42756 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
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