Mail settings' command parameter injection in mybb
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-77.
Summary
MyBB is a free and open source forum software. The _Mail Settings_ → Additional Parameters for PHP's mail() function mail_parameters setting value, in connection with the configured mail program's options and behavior, may allow access to sensitive information and Remote Code Execution (RCE). The vulnerable module requires Admin CP access with the `_Can manage settings?_` permission and may depend on configured file permissions. MyBB 1.8.31 resolves this issue with the commit `0cd318136a`. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA mybb (mybb) Fixed in 1.8.31
Timeline
- 2026-10-02 Threatist record created from CVE-2022-39265
References
More Mybb vulnerabilities
- TI-2011-04621 myBB 1.6.4 Backdoor Arbitrary Command Execution CVSS 4.0CRITICAL 10.0
- TI-2022-08548 Remote code execution in mybb CVSS 3.1HIGH 7.2
- TI-2023-21959 MyBB before 1.8.36 allows Code Injection by users with certain high privileges. CVSS 3.1HIGH 7.2
- TI-2025-21092 An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the… CVSS 3.1HIGH 7.6
- TI-2025-21091 An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the… CVSS 3.1HIGH 7.6
- TI-2025-21090 An issue in MyBB 1.8.38 allows a remote attacker to obtain sensitive information via the… CVSS 3.1HIGH 7.6
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences