CVE-2025-4855

Support Board <= 3.8.0 - Unauthenticated Authorization Bypass due to Use of Default Secret Key

2025-07-08 10:43
Foxyyy

Strategic Overview

Status
Patched in 3.8.1
Affected Plugin
Support Board
Affected Version
<= 3.8.0
CVSS
9.8Critical
Weakness type
CWE-639 · Authorization Bypass Through User-Controlled Key
CVE
CVE-2025-4855
View all Support Board vulnerabilities

At a glance

CVE-2025-4855 is a critical-severity Authorization Bypass Through User-Controlled Key vulnerability in the Support Board WordPress plugin, affecting versions <= 3.8.0. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 3.8.1; sites on affected versions should update now. Disclosed July 2025, reported by Foxyyy.

Vulnerability Overview

The Support Board plugin for WordPress is vulnerable to unauthorized access/modification/deletion of data due to use of hardcoded default secrets in the sb_encryption() function in all versions up to, and including, 3.8.0. This makes it possible for unauthenticated attackers to bypass authorization and execute arbitrary AJAX actions defined in the sb_ajax_execute() function. An attacker can use this vulnerability to exploit CVE-2025-4828 and various other functions unauthenticated.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-639: Authorization Bypass Through User-Controlled Key

Support Board <= 3.8.0 carries this weakness at sb_encryption(), and reaching it takes no account at all. Authorization bypass through a user-controlled key, often called insecure direct object reference, means the application looks up a record by an identifier from the request without checking that the caller owns it.

Changing a number in the request is enough to read or modify other users' records, which on commerce and membership sites means customer data. For Support Board the fix is 3.8.1: builds <= 3.8.0 are affected, anything from 3.8.1 onward is not.

Remediation

Update to version 3.8.1, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: Support Board 3.8.1 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2025-4855https://www.wordfence.com/threat-intel/vulnerabilities/id/afd48bc8-d490-4a3e-97fc-70cf008cbf66https://nvd.nist.gov/vuln/detail/CVE-2025-4855

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C