Vulnerability · CVE-2021-47741
ZBL EPON ONU Broadband Router V100R001 contains a privilege escalation vulnerability that allows limited administrative users to elevate access by sending requests to configuration
Published Dec 31, 2025 · catalog updated Jan 2, 2026 · Zblchina ZBL EPON ONU Broadband Router
Last checked Nov 3, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2021-47741. EPSS is 0.29%. Act only if a listed version of Zblchina ZBL EPON ONU Broadband Router is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High8.7
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.29%
- Remediation
- Vendor / distro source
- Affected products
- vendor Zblchina ZBL EPON ONU Broadband Router 1.0
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor Zblchina ZBL EPON ONU Broadband Router 1.01.0
How to fix CVE-2021-47741
No stored fix
No vendor fix text is stored. Use the linked advisory before you change production.
Version check
Seen in 1.0
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2021-47741. EPSS is 0.29%. Act only if a listed version of Zblchina ZBL EPON ONU Broadband Router is installed.
Which versions are affected?
Compare what you have installed with Zblchina ZBL EPON ONU Broadband Router 1.0 1.0. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.29%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Dec 31, 2025 · EUVD
Detected
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.
Jan 2, 2026 · EUVD
Updated
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.
Sources
- CVE.orgVulnerability recordCVE-2021-47741
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2021-47741
30-day exploitation probability 0.29%
first.org - EUVDVulnerability recordEUVD-2025-206085
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 passwor
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Nov 3, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSNov 3, 2026
- CVE.orgOct 31, 2026
- EUVDOct 31, 2026