Zblchina ZBL EPON ONU Broadband Router V100R001 Configuration Backup insufficiently protected credentials

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.0$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Zblchina ZBL EPON ONU Broadband Router V100R001. Affected by this issue is some unknown functionality of the component Configuration Backup Handler. Executing a manipulation can lead to insufficiently protected credentials. This vulnerability appears as CVE-2021-47741. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Zblchina ZBL EPON ONU Broadband Router V100R001. It has been declared as critical. This vulnerability affects some unknown functionality of the component Configuration Backup Handler. The manipulation with an unknown input leads to a insufficiently protected credentials vulnerability. The CWE definition for the vulnerability is CWE-522. The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was presented by Gjoko Krstic as 49737. The advisory is shared for download at exploit-db.com. This vulnerability was named CVE-2021-47741 since 12/23/2025. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 01/01/2026). The MITRE ATT&CK project declares the attack technique as T1552.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-206085). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.0

VulDB Base Score: 8.8
VulDB Temp Score: 8.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Insufficiently protected credentials
CWE: CWE-522
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

12/23/2025 CVE reserved
12/31/2025 +8 days Advisory disclosed
12/31/2025 +0 days VulDB entry created
01/01/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: 49737
Researcher: Gjoko Krstic
Status: Not defined

CVE: CVE-2021-47741 (🔒)
GCVE (CVE): GCVE-0-2021-47741
GCVE (VulDB): GCVE-100-339208
EUVD: 🔒

Entryinfo

Created: 12/31/2025 19:59
Updated: 01/01/2026 23:01
Changes: 12/31/2025 19:59 (77), 01/01/2026 23:01 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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