JVN#17127920
Smart TV Box fails to restrict access permissions
Overview
Smart TV Box fails to restrict access permissions.
Products Affected
- Smart TV Box firmware version prior to 1300
Description
Smart TV Box provided by KDDI CORPORATION enables access to Android Debug Bridge via port 5555/TCP of LAN side interface.
When a cable television provider sets up Smart TV Box at an individual residence, direct access from outside to the LAN side interface of Smart TV Box is disabled. However if the original setting is changed later, for example, LAN side interface connection to internet directly is enabled, access to Android Debug Bridge via port 5555/TCP of LAN side interface becomes enabled. As a result, arbitrary operations without users intent becomes possible, and a remote attacker may conduct arbitrary operations on the device (CWE-284).
Impact
A remote attacker may conduct arbitrary operations on the device without user's intent, such as installing arbitrary software or changing the device settings.
Solution
Update the Firmware
Update the firmware to the latest version according to the information provided by the developer.
The developer also suggests that a user should check the appropriate network settings of the device by following the guidance provided by the developer.
Vendor Status
| Vendor | Status | Last Update | Vendor Notes |
|---|---|---|---|
| KDDI CORPORATION | Vulnerable | 2019/08/23 | KDDI CORPORATION website |
References
JPCERT/CC Addendum
This analysis assumes that direct access via internet to the device is enabled by changing the original settings.
Vulnerability Analysis by JPCERT/CC
| Attack Vector(AV) | Physical (P) | Local (L) | Adjacent (A) | Network (N) |
|---|---|---|---|---|
| Attack Complexity(AC) | High (H) | Low (L) | ||
| Privileges Required(PR) | High (H) | Low (L) | None (N) | |
| User Interaction(UI) | Required (R) | None (N) | ||
| Scope(S) | Unchanged (U) | Changed (C) | ||
| Confidentiality Impact(C) | None (N) | Low (L) | High (H) | |
| Integrity Impact(I) | None (N) | Low (L) | High (H) | |
| Availability Impact(A) | None (N) | Low (L) | High (H) |
| Access Vector(AV) | Local (L) | Adjacent Network (A) | Network (N) |
|---|---|---|---|
| Access Complexity(AC) | High (H) | Medium (M) | Low (L) |
| Authentication(Au) | Multiple (M) | Single (S) | None (N) |
| Confidentiality Impact(C) | None (N) | Partial (P) | Complete (C) |
| Integrity Impact(I) | None (N) | Partial (P) | Complete (C) |
| Availability Impact(A) | None (N) | Partial (P) | Complete (C) |
Credit
Yoshiki Mori and Masaki Kubo of Cybersecurity Laboratory, National Institute of Information and Communications Technology reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.
Other Information
| JPCERT Alert | |
| JPCERT Reports | |
| CERT Advisory | |
| CPNI Advisory | |
| TRnotes | |
| CVE |
CVE-2019-6005 |
| JVN iPedia |
JVNDB-2019-000053 |