Observium PHP Object Unserialization Remote File Writing Vulnerability

critical Nessus Plugin ID 95391

Synopsis

The remote Observium server is affected by a remote file writing vulnerability.

Description

The remote Observium server is affected by a remote file writing vulnerability in the var_decode() function in common.inc.php due to improper validation of user-supplied GET, POST and COOKIE values before use in the PHP unserialize() function. An unauthenticated, remote attacker can exploit this to write data to arbitrary files, including a PHP session file that allows the attacker to gain administrative privileges.

Note that Observium is reportedly affected by additional vulnerabilities; however, Nessus has not tested for these.

Solution

Upgrade to an Observium version released on or after 2016/10/26.

See Also

https://www.computest.nl/advisories/CT-2016-1110_Observium.txt

Plugin Details

Severity: Critical

ID: 95391

File Name: observium_unserialize.nasl

Version: 1.7

Type: remote

Family: CGI abuses

Published: 11/29/2016

Updated: 11/15/2018

Supported Sensors: Nessus

Risk Information

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.3

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

CVSS v3

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:X

Vulnerability Information

CPE: x-cpe:/a:observium_limited:observium

Required KB Items: installed_sw/Observium

Exploited by Nessus: true

Patch Publication Date: 10/26/2016

Vulnerability Publication Date: 11/10/2016