An issue was discovered on Dasan GPON home routers. It is possible to bypass authentication simply by appending "?images" to any URL of the device that requires authentication, as demonstrated by the /menu.html?images/ or /GponForm/diag_FORM?images/ URI. One can then manage the device.
An issue was discovered on Dasan GPON home routers. It is possible to bypass authentication simply by appending "?images" to any URL of the device that requires authentication, as demonstrated by the /menu.html?images/ or /GponForm/diag_FORM?images/ URI. One can then manage the device.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 98.00 |
| Exploitation signal(KEV listed) | ×1.50 |
| VPI | 100.00 |
VPI formula vpi-v1
Required Action
The impacted product is end-of-life and should be disconnected if still in use.
| Source | CVSS Version | Base Score | Severity | Vector String | Assessment Date |
|---|---|---|---|---|---|
| NVDNIST | 3.1 | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | 04/20/2026 |
| NVDNIST | 2.0 | 7.5 |
| AV:N/AC:L/Au:N/C:P/I:P/A:P |
| 04/20/2026 |