Table of Contents
Why won’t my Keybox file pass Strong Integrity starting April 2026?
If you currently rely on rooting modules like Tricky Store or PIF (Play Integrity Fix) to access banking applications, you must prepare for a significant disruption. For years, the standard procedure involved placing an unrevoked Keybox file into the data > adb > tricky_store directory. This method successfully spoofed the system, allowing devices with unlocked bootloaders to pass Strong Integrity checks.
However, Google is implementing architectural changes to the Android security model. Effective February 2026, these Keybox files will likely cease functioning for devices running Android 13 and newer.
The Technical Shift: Remote Key Provisioning (RKP)
The root cause of this disruption is the mandatory enforcement of Remote Key Provisioning (RKP). Previously, rooted users could utilize leaked OEM keys to mimic a secure environment. This loophole is closing.
Google is transitioning the cryptographic standard used for device attestation. RKP servers will begin issuing keys signed with a new RSA-4096 attestation signing root certificate. This creates a compatibility conflict for modified devices:
- Mandatory RKP: Devices launched with Android 13 or higher must use RKP.
- Root Certificate Mismatch: Phones with unlocked bootloaders cannot authenticate against the new RSA-4096 root.
- Blocking of Legacy Keys: Leaked OEM keys used by tools like TrickyStore rely on the older RSA-2048 root. Once the server enforcement begins, these legacy keys will fail to generate valid Device or Strong Integrity verdicts.
This change affects hardware backed by both broken and unbroken Trusted Execution Environments (TEE).
Implementation Timeline
The transition is not instantaneous but will occur over a strict window. The timeline relies on the expiration cycle of RKP certificates:
- February 2026: Devices using RKP begin receiving certificates rooted in the new RSA-4096 standard.
- February to April 2026: A transition period occurs. Current certificates have a lifespan of approximately two months (gradually reducing to 45 days).
- April 10, 2026: This is the projected hard deadline. By this date, all RKP-enabled devices must use the new root. The infrastructure will block the old RSA-2048 root, rendering current bypass methods ineffective.
The Pixel 6 Exception
A notable exception to this enforcement appears to be the Google Pixel 6 series.
These devices will likely remain on the whitelist and continue using the older RSA-2048 attestation root. This exception exists due to a hardware anomaly involving the Titan M2 security chip. The Pixel 6’s early StrongBox firmware lacks native RKP support, forcing the device to rely on the standard TEE for attestation. Because the hardware cannot physically support the new migration path, Google must allow these specific devices to function using the legacy protocol.