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	Add content from: SoTap: Lightweight in-app JNI (.so) behavior logger for Andr...
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				@ -171,6 +171,18 @@ When the information is saved in logs you can **check statistics like how many t
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---
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### Android in-app native telemetry (no root)
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On Android, you can instrument native code inside the target app process by preloading a tiny logger library before other JNI libs initialize. This gives early visibility into native behavior without system-wide hooks or root. A popular approach is SoTap: drop libsotap.so for the right ABI into the APK and inject a System.loadLibrary("sotap") call early (e.g., static initializer or Application.onCreate), then collect logs from internal/external paths or Logcat fallback.
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See the Android native reversing page for setup details and log paths:
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{{#ref}}
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../../../mobile-pentesting/android-app-pentesting/reversing-native-libraries.md
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{{#endref}}
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---
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## Deobfuscating Dynamic Control-Flow (JMP/CALL RAX Dispatchers)
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Modern malware families heavily abuse Control-Flow Graph (CFG) obfuscation: instead of a direct jump/call they compute the destination at run-time and execute a `jmp rax` or `call rax`.  A small *dispatcher* (typically nine instructions) sets the final target depending on the CPU `ZF`/`CF` flags, completely breaking static CFG recovery.
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@ -262,5 +274,6 @@ idc.set_callee_name(call_ea, resolved_addr, 0)  # IDA 8.3+
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## References
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- [Unit42 – Evolving Tactics of SLOW#TEMPEST: A Deep Dive Into Advanced Malware Techniques](https://unit42.paloaltonetworks.com/slow-tempest-malware-obfuscation/)
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- SoTap: Lightweight in-app JNI (.so) behavior logger – [github.com/RezaArbabBot/SoTap](https://github.com/RezaArbabBot/SoTap)
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{{#include ../../banners/hacktricks-training.md}}
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@ -63,6 +63,42 @@ Java.perform(function () {
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```
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Frida will work out of the box on PAC/BTI-enabled devices (Pixel 8/Android 14+) as long as you use frida-server 16.2 or later – earlier versions failed to locate padding for inline hooks.  
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### Process-local JNI telemetry via preloaded .so (SoTap)
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When full-featured instrumentation is overkill or blocked, you can still gain native-level visibility by preloading a small logger inside the target process. SoTap is a lightweight Android native (.so) library that logs the runtime behavior of other JNI (.so) libraries within the same app process (no root required).
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Key properties:
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- Initializes early and observes JNI/native interactions inside the process that loads it.
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- Persists logs using multiple writable paths with graceful fallback to Logcat when storage is restricted.
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- Source-customizable: edit sotap.c to extend/adjust what gets logged and rebuild per ABI.
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Setup (repack the APK):
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1) Drop the proper ABI build into the APK so the loader can resolve libsotap.so:
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   - lib/arm64-v8a/libsotap.so (for arm64)
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   - lib/armeabi-v7a/libsotap.so (for arm32)
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2) Ensure SoTap loads before other JNI libs. Inject a call early (e.g., Application subclass static initializer or onCreate) so the logger is initialized first. Smali snippet example:
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   ```smali
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   const-string v0, "sotap"
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   invoke-static {v0}, Ljava/lang/System;->loadLibrary(Ljava/lang/String;)V
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   ```
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3) Rebuild/sign/install, run the app, then collect logs.
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Log paths (checked in order):
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```
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/data/user/0/%s/files/sotap.log
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/data/data/%s/files/sotap.log
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/sdcard/Android/data/%s/files/sotap.log
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/sdcard/Download/sotap-%s.log
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# If all fail: fallback to Logcat only
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```
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Notes and troubleshooting:
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- ABI alignment is mandatory. A mismatch will raise UnsatisfiedLinkError and the logger won’t load.
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- Storage constraints are common on modern Android; if file writes fail, SoTap will still emit via Logcat.
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- Behavior/verbosity is intended to be customized; rebuild from source after editing sotap.c.
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This approach is useful for malware triage and JNI debugging where observing native call flows from process start is critical but root/system-wide hooks aren’t available.
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---
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### Recent vulnerabilities worth hunting for in APKs
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@ -93,6 +129,9 @@ When you spot *third-party* `.so` files inside an APK, always cross-check their
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### References
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- Frida 16.x change-log (Android hooking, tiny-function relocation) – [frida.re/news](https://frida.re/news/)  
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- NVD advisory for `libwebp` overflow CVE-2023-4863 – [nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2023-4863) 
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- NVD advisory for `libwebp` overflow CVE-2023-4863 – [nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2023-4863)
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- SoTap: Lightweight in-app JNI (.so) behavior logger – [github.com/RezaArbabBot/SoTap](https://github.com/RezaArbabBot/SoTap)
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- SoTap Releases – [github.com/RezaArbabBot/SoTap/releases](https://github.com/RezaArbabBot/SoTap/releases)
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- How to work with SoTap? – [t.me/ForYouTillEnd/13](https://t.me/ForYouTillEnd/13)
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{{#include ../../banners/hacktricks-training.md}}
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{{#include ../../banners/hacktricks-training.md}}
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@ -1,4 +1,4 @@
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# Smali - Decompiling/\[Modifying]/Compiling
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# Smali - Decompiling/[Modifying]/Compiling
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{{#include ../../banners/hacktricks-training.md}}
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@ -25,7 +25,7 @@ If **apktool** gives you any error, try[ installing the **latest version**](http
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Some **interesting files you should look are**:
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- _res/values/strings.xml_ (and all xmls inside res/values/\*)
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- _res/values/strings.xml_ (and all xmls inside res/values/*)
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- _AndroidManifest.xml_
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- Any file with extension _.sqlite_ or _.db_
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@ -162,7 +162,7 @@ invoke-static {v5, v1}, Landroid/util/Log;->d(Ljava/lang/String;Ljava/lang/Strin
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Recommendations:
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- If you are going to use declared variables inside the function (declared v0,v1,v2...) put these lines between the _.local \<number>_ and the declarations of the variables (_const v0, 0x1_)
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- If you are going to use declared variables inside the function (declared v0,v1,v2...) put these lines between the _.local <number>_ and the declarations of the variables (_const v0, 0x1_)
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- If you want to put the logging code in the middle of the code of a function:
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  - Add 2 to the number of declared variables: Ex: from _.locals 10_ to _.locals 12_
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  - The new variables should be the next numbers of the already declared variables (in this example should be _v10_ and _v11_, remember that it starts in v0).
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@ -186,8 +186,42 @@ move-result-object v12
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invoke-virtual {v12}, Landroid/widget/Toast;->show()V
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```
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### Loading a Native Library at Startup (System.loadLibrary)
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{{#include ../../banners/hacktricks-training.md}}
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Sometimes you need to preload a native library so it initializes before other JNI libs (e.g., to enable process-local telemetry/logging). You can inject a call to System.loadLibrary() in a static initializer or early in Application.onCreate(). Example smali for a static class initializer (<clinit>):
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```smali
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.class public Lcom/example/App;
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.super Landroid/app/Application;
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.method static constructor <clinit>()V
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    .registers 1
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    const-string v0, "sotap"         # library name without lib...so prefix
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    invoke-static {v0}, Ljava/lang/System;->loadLibrary(Ljava/lang/String;)V
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    return-void
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.end method
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```
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Alternatively, place the same two instructions at the start of your Application.onCreate() to ensure the library loads as early as possible:
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```smali
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.method public onCreate()V
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    .locals 1
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    const-string v0, "sotap"
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    invoke-static {v0}, Ljava/lang/System;->loadLibrary(Ljava/lang/String;)V
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    invoke-super {p0}, Landroid/app/Application;->onCreate()V
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    return-void
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.end method
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```
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Notes:
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- Make sure the correct ABI variant of the library exists under lib/<abi>/ (e.g., arm64-v8a/armeabi-v7a) to avoid UnsatisfiedLinkError.
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- Loading very early (class static initializer) guarantees the native logger can observe subsequent JNI activity.
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## References
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- SoTap: Lightweight in-app JNI (.so) behavior logger – [github.com/RezaArbabBot/SoTap](https://github.com/RezaArbabBot/SoTap)
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{{#include ../../banners/hacktricks-training.md}}
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