MyBB < 1.8.6 Arbitrary Code Execution

critical Nessus Network Monitor Plugin ID 9946
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The remote web server is running a PHP application that is vulnerable to an arbitrary code execution attack vector.


Versions of MyBB (MyBulletinBoard) prior to 1.8.6 are affected by a flaw in the '__wakeup()' method that is triggered when deserializing specially crafted GMP objects. This may allow a remote attacker to potentially execute arbitrary code.


Upgrade to MyBB version 1.8.6 or later.

See Also

Plugin Details

Severity: Critical

ID: 9946

Family: CGI

Published: 2/9/2017

Updated: 3/6/2019

Dependencies: 9126

Risk Information


Risk Factor: Critical

Base Score: 10

Temporal Score: 8.3

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:F/RL:OF/RC:C


Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9.1

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:F/RL:O/RC:C

Vulnerability Information

CPE: cpe:2.3:a:mybb:mybb:*:*:*:*:*:*:*:*

Patch Publication Date: 2/15/2015

Vulnerability Publication Date: 1/21/2017