Vbulletin
CVE-2023-25135
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A08:2025 - Software or Data Integrity Failures
ASVS 5.0
V1 - Encoding and Sanitization Safe deserialization, type allowlists
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | A remote attacker could execute arbitrary code through malicious serialized objects by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
vBulletin before 5.6.9 PL1 allows an unauthenticated remote attacker to execute arbitrary code via a crafted HTTP request that triggers deserialization. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Avoid deserializing untrusted data. Use safe serialization formats (JSON). Implement integrity checks and type allowlists.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Deserialization of Untrusted Data (CWE-502), which allows attackers to execute arbitrary code through malicious serialized objects. vBulletin before 5.6.9 PL1 allows an unauthenticated remote attacker to execute arbitrary code via a crafted HTTP request that triggers deserialization. This occurs because verify_serialized checks that a value is serialized by calling unserialize and then checking for errors. The fixed versions are 5.6.7 PL1, 5.6.8 PL1, and 5.6.9 PL1. Affected products include: Vbulletin. Version information: before 5.6.9.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
vBulletin before 5.6.9 PL1 allows an unauthenticated remote attacker to execute arbitrary code via a crafted HTTP request that triggers deserialization. This occurs because verify_serialized checks that a value is serialized by calling unserialize and then checking for errors. The fixed versions are 5.6.7 PL1, 5.6.8 PL1, and 5.6.9 PL1.
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
Insecure deserialization occurs when an application converts serialized data (a stream of bytes representing an object's state) back into a living object without proper validation.
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)NVD
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
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 protec
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
GitHub PoC
Exploit-DB