Vbulletin
CVE-2025-48828
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Alternate path protection
|
| Impact | CVSS 10.0, EPSS 69.4%, PoC available, actively exploited. This vulnerability specifically affects vBulletin installations running on PHP 8.1+, which is increasingly common as hosting providers upgrade PHP versions. The API access bypass can chain with CVE-2025-48828 (template injection) for full RCE. |
| Exploit ScenarioDerived | An attacker sends requests to /api.php targeting protected methods on vBulletin's API controllers. They access user management functions to enumerate accounts, modify user roles, or extract sensitive data. Combined with the template injection vulnerability, they achieve full remote code execution and dump the forum database. |
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Alert meAnalysisAIv1 – Mar 28, 2026
vBulletin 5.0.0 through 5.7.5 and 6.0.0 through 6.0.3 running on PHP 8.1 or later allow unauthenticated access to protected API controllers. The /api.php endpoint fails to properly enforce method visibility on PHP 8.1+, enabling attackers to invoke internal API methods that should be restricted, as exploited in the wild in May 2025.
Earlier versions of this analysis (1)
Unauthenticated API access bypass in vBulletin on PHP 8.1+ allows invocation of protected controller methods, exploited in the wild.
RemediationAI
Update to vBulletin 5.7.6 or 6.0.4. If immediate patching is not possible, restrict access to /api.php at the web server level. Monitor API access logs for requests to protected methods. Consider temporarily downgrading to PHP 8.0 as a mitigation.
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Technical ContextAI · show details
PHP 8.1 introduced changes to reflection and method visibility handling that affect how vBulletin's API routing validates accessible methods. Protected methods on API controllers that should be unreachable by external requests become invocable through the /api.php?method=protectedMethod pattern. This bypasses intended access controls and exposes internal API functionality to unauthenticated users.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
Lifecycle Timeline
2DescriptionCVE.org
Certain vBulletin versions might allow attackers to execute arbitrary PHP code by abusing Template Conditionals in the template engine. By crafting template code in an alternative PHP function invocation syntax, such as the "var_dump"("test") syntax, attackers can bypass security checks and execute arbitrary PHP code, as exploited in the wild in May 2025.
Executive ViewAI
Organizations using vBulletin face critical risk from CVE-2025-48828 rated CVSS 9.0. Successful exploitation could critically impact the confidentiality, integrity, and availability of affected systems. With an EPSS score of 74%, this vulnerability faces very high likelihood of exploitation. Organizations should apply vendor updates immediately when available and implement compensating controls in the interim.
Apply vendor patch. If immediate patching is not feasible: (1) Implement network-level access controls to limit exposure; (2) Enable enhanced monitoring and alerting; (3) Apply principle of least privilege.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)CVE.org
vBulletin versions 5.0.0 through 5.7.5 and 6.0.0 through 6.0.3 are vulnerable to remote code execution through crafted t
SQL injection vulnerability in forumrunner/includes/moderation.php in vBulletin before 4.2.2 Patch Level 5 and 4.2.3 bef
The vB_Api_Hook::decodeArguments method in vBulletin 5 Connect 5.1.2 through 5.1.9 allows remote attackers to conduct PH
The install/upgrade.php scripts in vBulletin 4.1 and 5 allow remote attackers to create administrative accounts via the
SQL injection vulnerability in index.php/ajax/api/reputation/vote in vBulletin 5.0.0 Beta 11, 5.0.0 Beta 28, and earlier
vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data in an ajax/render/widget_tabbe
vBulletin before 5.5.6pl1, 5.6.0 before 5.6.0pl1, and 5.6.1 before 5.6.1pl1 has incorrect access control. Rated critical
vBulletin 5.x through 5.5.4 allows remote command execution via the widgetConfig[code] parameter in an ajax/render/widge
In vBulletin through 5.3.x, there is an unauthenticated deserialization vulnerability that leads to arbitrary file delet
The media-file upload feature in vBulletin before 3.8.7 Patch Level 6, 3.8.8 before Patch Level 2, 3.8.9 before Patch Le
vBulletin through 5.3.x on Windows allows remote PHP code execution because a require_once call is reachable with an una
vBulletin before 5.6.9 PL1 allows an unauthenticated remote attacker to execute arbitrary code via a crafted HTTP reques
GitHub PoC
Exploit-DB