Mybb
CVE-2016-9412
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Access control enforcement
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion 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. EPSS exploitation probability: 2.85%. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system. |
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Alert meAnalysisAI
MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allow attackers to have unspecified impact via vectors related to low adminsid and sid entropy. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
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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 under CWE-284. MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allow attackers to have unspecified impact via vectors related to low adminsid and sid entropy. Affected products include: Mybb Merge System, Mybb. Version information: before 1.8.7.
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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
DescriptionCVE.org
MyBB (aka MyBulletinBoard) before 1.8.7 and MyBB Merge System before 1.8.7 allow attackers to have unspecified impact via vectors related to low adminsid and sid entropy.
Threat Intelligence Overview
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
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)CVE.org
MyBB is a free and open source forum software. Rated high severity (CVSS 7.2), this vulnerability is remotely exploitabl
The installer in MyBB before 1.8.13 allows remote attackers to execute arbitrary code by writing to the configuration fi
SQL Injection vulnerability in MyBB before 1.8.26 via poll vote count. Rated high severity (CVSS 8.8), this vulnerabilit
SQL Injection vulnerablity in MyBB before 1.8.26 via theme properties included in theme XML files. Rated high severity (
In MyBB before 1.8.21, an attacker can exploit a parsing flaw in the Private Message / Post renderer that leads to [vide
Privilege escalation in MyBB 1.8.40 lets a limited Admin Control Panel (ACP) user who holds only the delegated user-mana
MyBB before 1.8.11 allows remote attackers to bypass an SSRF protection mechanism. Rated high severity (CVSS 7.7), this
SQL injection vulnerability in member.php in MyBB (aka MyBulletinBoard) 1.8.x before 1.8.2 allows remote attackers to ex
An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the Change Avatar function. Rated h
An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the Import a Theme function. Rated
An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the Mail function. Rated high sever
Multiple SQL injection vulnerabilities in ajaxfs.php in the Ajax forum stat (Ajaxfs) Plugin 2.0 for MyBB (aka MyBulletin
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB