CVE-2021-47741

HIGH EPSS 15.8%
Published Dec 31, 20255mo ago · Modified Jun 17, 20261w ago
8.7 CVSS 4.0
High
Find Similar
Published Dec 31, 2025 5mo ago
Last Modified Jun 17, 2026 1w ago

Description

ZBL EPON ONU Broadband Router V100R001 contains a privilege escalation vulnerability that allows limited administrative users to elevate access by sending requests to configuration endpoints. Attackers can exploit the vulnerability by accessing the configuration backup or password page to disclose the super user password and gain additional privileged functionalities.

CVSS Details

Base Score
8.7
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
15.8% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-522

References 5

  • zblchina.com http://www.zblchina.com
  • web.archive.org https://web.archive.org/web/20211220094023/http://www.wd-thailand.com/
  • exploit-db.com https://www.exploit-db.com/exploits/49737
  • vulncheck.com https://www.vulncheck.com/advisories/zbl-epon-onu-broadband-router-vr-privilege-escalation-via-configuration-endpoint
  • zeroscience.mk https://www.zeroscience.mk/en/vulnerabilities/ZSL-2021-5647.php

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.