CVE-2025-4855 | Support Board <= 3.8.0 - Unauthenticated Authorization Bypass due to Use of Default Secret Key

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.

Published: 2025-07-09 Last update: 2025-07-14 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-4855 is rated High Risk (65.2/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 0.77%). High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-4855

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-04 0.46% 0.77% +0.31%
2 2026-04-24 0.42% 0.46% +0.04%
3 2026-04-03 — 0.42% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-4855

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]

Weakness enumeration for CVE-2025-4855

Affected software / configurations for CVE-2025-4855

Vendor Product Version Raw CPE
schiocco support_board < 3.8.1 cpe:2.3:a:schiocco:support_board:*:*:*:*:*:wordpress:*:*

References for CVE-2025-4855

cvelogic Threat Intelligence