An issue was discovered on FiberHome Fengine S5800 switches V210R240. An unauthorized attacker can access the device's SSH service, using a password cracking tool to establish SSH connections quickly. This will trigger an increase in the SSH login timeout (each of the login attempts will occupy a connection slot for a longer time). Once this occurs, legitimate login attempts via SSH/telnet will be refused, resulting in a denial of service; you must restart the device.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.9, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 6 products from fiberhome, from fiberhome, from fiberhome and 3 others, organizations running these solutions should prioritize assessment and patching.
First disclosed in 2017, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.
2017-01-23T07:59:00.547
2026-05-13T00:24:29.033
Modified
CVSSv3.1: 5.9 (MEDIUM)
AV:N/AC:M/Au:N/C:N/I:N/A:C
8.6
6.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | fiberhome | fengine_s5800_firmware | v210r240 | Yes |
| Hardware | fiberhome | fengine_28f-s | - | No |
| Hardware | fiberhome | fengine_52f-s | - | No |
| Hardware | fiberhome | fengine_52t-s | - | No |
| Hardware | fiberhome | fengine_s5800-28t-s | - | No |
| Hardware | fiberhome | fengine_s5800-28t-s-pe | - | No |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For fiberhome's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.