Skip to content
Fencer Vulns
medium 5.3

CVE-2026-8499 json

Helpfulcrowd Product Reviews <= 1.2.9 - Inccorect Authorization via Type Juggling in 'token' Parameter to Arbitrary Settings Update

published 2026-06-09 5 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-35302

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits
0
none known

Summary

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.

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected products

  • helpfulcrowd Helpfulcrowd Product Reviews

Classification

Weakness
  • CWE-843 Access of Resource Using Incompatible Type
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.