The routers lack authentication for certain web APIs, allowing anyone on the network to retrieve device information without credentials. If the device's administrative password remains set to the factory default, the attacker can gain full administrative control, effectively taking over the device. This issue is classified as an authentication bypass vulnerability (CWE-306).

Sharp Corporation's 5G Mobile Router SH-U01, Pocket WiFi 5G A503SH, Speed Wi-Fi 5G X01, Wi-Fi STATION SH-52A, Wi-Fi STATION SH-52B, Wi-Fi STATION SH-54C, home 5G HR01, and home 5G HR02 are impacted. Version information is not specified, but all models shipped before the recent advisory are potentially vulnerable.

The CVSS score of 6.9 indicates a medium-to-high severity. With no credentials required, an attacker who can reach the device over the network can automatically access the vulnerable endpoints, retrieve configuration data, and, if default credentials are still in use, assume administrative privileges. While the EPSS score is not available and the vulnerability is not listed in KEV, the lack of authentication makes exploitation straightforward and the potential impact significant.