#VU16041 Phar deserialization in phpBB


Published: 2018-11-23 | Updated: 2018-11-23

Vulnerability identifier: #VU16041

Vulnerability risk: Low

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-19274

CWE-ID: CWE-502

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
phpBB
Web applications / Forum & blogging software

Vendor: phpBB Group

Description
The vulnerability allows a remote attacker with administrator privileges to execute arbitrary PHP code.

The weakness exists in a feature that utilizes an image editor binary called Imagick due to Phar deserialization if user input is passed unsanitized to any file system function in PHP, such as file_exists(). A remote attacker with access to the Admin Control Panel with founder permissions can upload a malicious image file and edit it with Imagick to execute arbitrary PHP code on the underlying server and then to perform a full site takeover.

Mitigation
Update to version 3.2.4.

Vulnerable software versions

phpBB: 3.2.0 - 3.2.3


External links
http://blog.ripstech.com/2018/phpbb3-phar-deserialization-to-remote-code-execution/


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.


Latest bulletins with this vulnerability