[Android] StorageCipher initialization failed after upgrading to v10.x - Certificate not found in KeyStore

[sst4tic]

After upgrading flutter_secure_storage from an earlier version to 10.0.0+, our Android app crashes after update from version 9+ to 10.0.0 a StorageCipher initialization failed error. The root cause is that the certificate cannot be found in the Android KeyStore, which prevents the plugin from initializing properly.

Environment

Flutter doctor outputs

[✓] Flutter (Channel stable, 3.41.2, on macOS 26.2 25C56 darwin-arm64, locale ru-KZ)
[✓] Android toolchain - develop for Android devices (Android SDK version 35.0.0)
[✓] Xcode - develop for iOS and macOS (Xcode 26.0.1)
[✓] Chrome - develop for the web
[✓] Connected device (4 available)
[✓] Network resources

• No issues found!
st4tic@MacBook-Pro-Evgenij prosper-flutter-frontend % flutter doctor -v 
[✓] Flutter (Channel stable, 3.41.2, on macOS 26.2 25C56 darwin-arm64, locale ru-KZ) [277ms]
    • Flutter version 3.41.2 on channel stable at /Users/st4tic/development/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 90673a4eef (13 days ago), 2026-02-18 13:54:59 -0800
    • Engine revision 6c0baaebf7
    • Dart version 3.11.0
    • DevTools version 2.54.1
    • Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, cli-animations, enable-native-assets, omit-legacy-version-file, enable-lldb-debugging,
      enable-uiscene-migration

[✓] Android toolchain - develop for Android devices (Android SDK version 35.0.0) [1 022ms]
    • Android SDK at /Users/st4tic/Library/Android/sdk
    • Emulator version 36.2.12.0 (build_id 14214601) (CL:N/A)
    • Platform android-36, build-tools 35.0.0
    • ANDROID_HOME = /Users/st4tic/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
      This is the JDK bundled with the latest Android Studio installation on this machine.
      To manually set the JDK path, use: `flutter config --jdk-dir="path/to/jdk"`.
    • Java version OpenJDK Runtime Environment (build 21.0.8+-14018985-b1038.68)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 26.0.1) [756ms]
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 17A400
    • CocoaPods version 1.16.2

[✓] Chrome - develop for the web [4ms]
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

Error Logs

E/SecureStorageAndroid: re-encryption failed
E/SecureStorageAndroid: java.lang.Exception: No certificate found under alias: kz.prosperpay.app.FlutterSecureStoragePluginKey
    at B0.i.<init>(SourceFile:31)
    at E2.f.a(Unknown Source:13)
    at M2.a.f(Unknown Source:168)
    at M2.a.c(Unknown Source:18)
    at G.o.run(Unknown Source:455)
    at android.os.Handler.handleCallback(Handler.java:995)
    at android.os.Handler.dispatchMessage(Handler.java:103)
    at android.os.Looper.loopOnce(Looper.java:273)
    at android.os.Looper.loop(Looper.java:363)
    at android.os.HandlerThread.run(HandlerThread.java:85)

E/SecureStorageAndroid: StorageCipher initialization failed
E/SecureStorageAndroid: java.lang.Exception: No certificate found under alias: kz.prosperpay.app.FlutterSecureStoragePluginKey
    at B0.i.<init>(SourceFile:31)
    at E2.f.a(Unknown Source:13)
    at M2.a.f(Unknown Source:349)
    at M2.a.c(Unknown Source:18)
    at G.o.run(Unknown Source:455)
    at android.os.Handler.handleCallback(Handler.java:995)
    at android.os.Handler.dispatchMessage(Handler.java:103)
    at android.os.Looper.loopOnce(Looper.java:273)
    at android.os.Looper.loop(Looper.java:363)
    at android.os.HandlerThread.run(HandlerThread.java:85)

E/flutter: [ERROR:flutter/runtime/dart_vm_initializer.cc(40)] Unhandled Exception: PlatformException(Exception encountered, read, java.lang.NullPointerException: Attempt to invoke virtual method 'int B0.i.u()' on a null object reference
    at M2.a.b(Unknown Source:11)
    at G.o.run(Unknown Source:484)
    at android.os.Handler.handleCallback(Handler.java:995)
    at android.os.Handler.dispatchMessage(Handler.java:103)
    at android.os.Looper.loopOnce(Looper.java:273)
    at android.os.Looper.loop(Looper.java:363)
    at android.os.HandlerThread.run(HandlerThread.java:85)
, null)