dbcve.org
Type ConfusionWeakness · CWE-843

CVE-2026-8499

MEDIUM · 5.3 CVSS v3.1 Published 2026-06-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
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
The Helpfulcrowd Product Reviews plugin for WordPress is vulnerable to Authorization Bypass via PHP Type Juggling in versions up to, and including, 1.2.9. This is due to the `helpfulcrowd_validate_token()` function using a loose comparison operator (`!=`) instead of a strict comparison (`!==`) when validating the `token` parameter, while the corresponding REST route `/wp-json/helpfulcrowd/v1/update-settings` is registered with a `permission_callback` of `__return_true`, making it reachable by unauthenticated users; submitting a JSON boolean `true` as the `token` value causes PHP's loose comparison to evaluate as equal to the non-empty base64-encoded secret string, bypassing the check entirely. This makes it possible for unauthenticated attackers to invoke `helpfulcrowd_settings_endpoint()` and write arbitrary attacker-controlled key-value pairs directly into the `helpfulcrowd_options` WordPress database option via `update_option()` without any sanitization or allowlist filtering, enabling full unauthenticated modification of the plugin's stored configuration.

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 Helpfulcrowd Product Reviews WordPress plugin uses loose comparison (`!=`) instead of strict comparison (`!==`) in its token validation function, combined with a REST endpoint registered with `permission_callback` set to `__return_true`. By submitting a JSON boolean `true` as the token parameter, unauthenticated attackers can bypass authentication due to PHP's type juggling, allowing arbitrary configuration values to be written directly to the WordPress database via `update_option()`.

MitigationUpdate the plugin to a version greater than 1.2.9 which fixes the loose comparison vulnerability; as an immediate workaround, disable the plugin or block the `/wp-json/helpfulcrowd/v1/update-settings` endpoint at the web server level.

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
None
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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 Helpfulcrowd plugin is installed
    Check for the plugin directory at /wp-content/plugins/helpfulcrowd-product-reviews/ or list installed plugins via WordPress admin under Plugins > Installed Plugins
    Affected if The plugin directory exists in the WordPress plugins folder
  2. Identify installed plugin version
    Open the main plugin file (e.g., helpfulcrowd.php) and locate the Version header in the plugin comment block, or view the version in WordPress admin plugin list
    Affected if The reported version is 1.2.9 or lower (any version up to and including 1.2.9)
  3. Confirm vulnerable REST endpoint exists
    Send a GET request to /wp-json/helpfulcrowd/v1/update-settings without any authentication headers and check for a valid JSON response (rather than a 401/403 error)
    Affected if The endpoint returns a successful JSON response (indicating permission_callback allows public access)
  4. Test token validation bypass
    Send a POST request to /wp-json/helpfulcrowd/v1/update-settings with a JSON body containing "token": true (boolean) and observe whether the request succeeds in modifying options
    Affected if The request with boolean true as token is accepted and processes the update (proving type juggling bypass works)

A user is affected if the Helpfulcrowd Product Reviews plugin version is 1.2.9 or lower and the REST endpoint /wp-json/helpfulcrowd/v1/update-settings is accessible without authentication.

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 the plugin to a version greater than 1.2.9 which fixes the loose comparison vulnerability; as an immediate workaround, disable the plugin or block the `/wp-json/helpfulcrowd/v1/update-settings` endpoint at the web server level.

Recommended fix Moderate confidence

1.3.0 or latest version available from WordPress plugin repository

  1. Navigate to the WordPress admin dashboard
  2. Go to Plugins > Installed Plugins
  3. Locate the Helpfulcrowd Product Reviews plugin
  4. Check if an update is available and update to the latest version (1.3.0 or later)
  5. Alternatively, download the latest version from the official WordPress plugin repository at plugins.trac.wordpress.org

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

Have this fixed Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-8499 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2026-8499 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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