CVE-2021-47741: ZBL EPON ONU Broadband Router V100R001 Privilege Escalation via Configuration Endpoint

Security readout for executives and security teams

This vulnerability affects ZBL EPON ONU Broadband Router V100R001. A user with limited administrative access can reach configuration-related pages that expose the super-user password, enabling higher privileges. For businesses, the main risk is loss of control over affected edge routers and possible service disruption or unauthorized network changes. Exposure is most relevant where affected ZBL EPON ONU routers are deployed and their management interface is reachable by untrusted users or over the internet. Exploitation requires low-privilege administrative access, not anonymous access, based on the provided CVSS vector and description. Prioritize this for environments using the affected router model, especially ISPs, branch networks, or customer-premises deployments. The vulnerability can turn limited admin access into super-user control. If the product is unsupported or no patch is available, containment or replacement may be the practical risk-reduction path. Mitigation focus: Identify any ZBL EPON ONU Broadband Router V100R001 devices in use.; Restrict router management access to trusted administration networks only.; Remove internet exposure for management interfaces wherever possible..

Prepared

Apr 30, 2026, 03:52 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.