Published:2026/10/14  Last Updated:2026/10/14

JVN#47427200
Multiple Rakuten Mobile smartphones shipped with a known private test key for Android Verified Boot

Overview

Multiple smartphones provided by Rakuten Mobile, Inc. utilize AOSP test keys for their Android Verified Boot (AVB) functionality.

Products Affected

  • Rakuten Mini all versions
  • Rakuten Hand all versions
  • Rakuten Hand 5G all versions
  • Rakuten BIGs all versions

Description

Multiple smartphones provided by Rakuten Mobile, Inc. utilize AOSP test keys for their Android Verified Boot (AVB) functionality.

  • Use of Weak Credentials (CWE-1391)
    • CVSS:4.0/AV:P/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N Base Score 7.0
    • CVSS:3.0/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Base Score 6.6
    • CVE-2026-107153

Impact

With physical access to the affected device, a crafted system image may be installed.

Solution

Stop using the products
Affected products are no longer supported. Stop using the vulnerable products and consider switching to alternatives.

Vendor Status

Vendor Link
Rakuten Mobile, Inc. Support Information for Rakuten Mini (Text in Japanese)
Support Information for Rakuten Hand (Text in Japanese)
Support Information for Rakuten Hand 5G (Text in Japanese)
Support Information for Rakuten Big s (Text in Japanese)

References

  1. Android-Device-Security.Org
    AVBTestKeyInTheWild: Bypassing Android Verified Boot Using A Firmware Supply Chain Vulnerability on Locked Devices

JPCERT/CC Addendum

Vulnerability Analysis by JPCERT/CC

Credit

Masayoshi Matsubara 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-2026-107153
JVN iPedia JVNDB-2026-000147