SQL Injection vulnerability in admin/batch_manager.php in piwigo v2.9.5, via the filter_category parameter to admin.php?page=batch_manager.
hi，There is a vulnerability in the admin/batch_manager.php.
![image](https://user-images.githubusercontent.com/34082644/57359656-d006db00-71aa-11e9-9f42-0509bafceed7.png)


I didn't find the full trigger request in the browser, so I added the ‘&filter_category_use=on’ parameter to the request based on the code.
```
POST /admin.php?page=batch_manager HTTP/1.1
Host: 10.150.10.186:30002
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: zh-CN,en-US;q=0.7,en;q=0.3
Accept-Encoding: gzip, deflate
Referer: http://10.150.10.186:30002/admin.php?page=batch_manager
Content-Type: application/x-www-form-urlencoded
Content-Length: 695
Cookie: pwg_display_thumbnail=no_display_thumbnail; pwg_id=85b6lvm6f6nqvji17k04ugkdu0
Connection: close
Upgrade-Insecure-Requests: 1

start=0&pwg_token=438d258aad10f5b13c74425475163e4e&filter_prefilter_use=on&filter_prefilter=last_import&filter_duplicate
s_date=on&filter_category=1&tag_mode=AND&filter_level=03&filter_dimension_min_width=145&filter_dimension_max_width=2560&
filter_dimension_min_height=91&filter_dimension_max_height=1440&filter_dimension_min_ratio=1.29&filter_dimension_max_rat
io=1.77&filter_search_use=on&q=&filter_filesize_use=on&filter_category_use=on&filter_filesize_min=1.3&filter_filesize_ma
x=1.3&submitFilter=&selectAction=-1&associate=1&dissociate=1&author=&title=&date_creation=2019-05-08+00%3A00%3A00&level=
0&regenerateSuccess=0&regenerateError=0
```
![image](https://user-images.githubusercontent.com/34082644/57359720-f62c7b00-71aa-11e9-9e85-507ef7179fff.png)
![image](https://user-images.githubusercontent.com/34082644/57359730-fcbaf280-71aa-11e9-9f31-6d84edf9a6af.png)
![image](https://user-images.githubusercontent.com/34082644/57359741-03e20080-71ab-11e9-8c2d-d279167aded3.png)
![image](https://user-images.githubusercontent.com/34082644/57359747-080e1e00-71ab-11e9-82a1-47ffc7557058.png)

SQL injection in admin/batch_manager.php
This is a GitHub Issue
repo:Piwigo
owner:Piwigo
Title : SQL injection in admin/batch_manager.php
Issue date:

--- start body ---
hi，There is a vulnerability in the admin/batch_manager.php.
![image](https://user-images.githubusercontent.com/34082644/57359656-d006db00-71aa-11e9-9f42-0509bafceed7.png)


I didn't find the full trigger request in the browser, so I added the ‘&filter_category_use=on’ parameter to the request based on the code.
```
POST /admin.php?page=batch_manager HTTP/1.1
Host: 10.150.10.186:30002
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: zh-CN,en-US;q=0.7,en;q=0.3
Accept-Encoding: gzip, deflate
Referer: http://10.150.10.186:30002/admin.php?page=batch_manager
Content-Type: application/x-www-form-urlencoded
Content-Length: 695
Cookie: pwg_display_thumbnail=no_display_thumbnail; pwg_id=85b6lvm6f6nqvji17k04ugkdu0
Connection: close
Upgrade-Insecure-Requests: 1

start=0&pwg_token=438d258aad10f5b13c74425475163e4e&filter_prefilter_use=on&filter_prefilter=last_import&filter_duplicate
s_date=on&filter_category=1&tag_mode=AND&filter_level=03&filter_dimension_min_width=145&filter_dimension_max_width=2560&
filter_dimension_min_height=91&filter_dimension_max_height=1440&filter_dimension_min_ratio=1.29&filter_dimension_max_rat
io=1.77&filter_search_use=on&q=&filter_filesize_use=on&filter_category_use=on&filter_filesize_min=1.3&filter_filesize_ma
x=1.3&submitFilter=&selectAction=-1&associate=1&dissociate=1&author=&title=&date_creation=2019-05-08+00%3A00%3A00&level=
0&regenerateSuccess=0&regenerateError=0
```
![image](https://user-images.githubusercontent.com/34082644/57359720-f62c7b00-71aa-11e9-9e85-507ef7179fff.png)
![image](https://user-images.githubusercontent.com/34082644/57359730-fcbaf280-71aa-11e9-9f31-6d84edf9a6af.png)
![image](https://user-images.githubusercontent.com/34082644/57359741-03e20080-71ab-11e9-8c2d-d279167aded3.png)
![image](https://user-images.githubusercontent.com/34082644/57359747-080e1e00-71ab-11e9-82a1-47ffc7557058.png)

--- end body ---
