CVE-2026-8499: The Helpfulcrowd Product Reviews plugin for WordPress is vulnerable to Authorization Bypass via PHP Type Juggling in versions up to, and including, 1....

Description

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.

Metrics

CVSS 3.1

5.3/10

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

EPSS Probability

0.27%

19.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-843

References

Timeline

Published: Jun 9, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-8499?

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.

How severe is CVE-2026-8499?

CVE-2026-8499 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2026-8499?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.