base on Utilizing TLS callbacks to execute a payload without spawning any threads in a remote process # Maldev Academy - RemoteTLSCallbackInjection ## Quick Links [Maldev Academy Home](https://maldevacademy.com) [Maldev Academy Syllabus](https://maldevacademy.com/syllabus) ## Related Maldev Academy Modules [New Module 34: TLS Callbacks For Anti-Debugging](https://maldevacademy.com/new/modules/34) [New Module 35: Threadless Injection](https://maldevacademy.com/new/modules/35) ## Overview This method utilizes TLS callbacks to execute a payload without spawning any threads in a remote process. This method is inspired by [Threadless Injection](https://github.com/CCob/ThreadlessInject/tree/master) as RemoteTLSCallbackInjection does not invoke any API calls to trigger the injected payload. ## Implementation Steps The PoC follows these steps: 1. Create a suspended process using the `CreateProcessViaWinAPIsW` function (i.e. `RuntimeBroker.exe`). 2. Fetch the remote process image base address followed by reading the process's PE headers. 3. Fetch an address to a TLS callback function. 4. Patch a fixed shellcode (i.e. [g_FixedShellcode](https://github.com/Maldev-Academy/RemoteTLSCallbackInjection/blob/main/RemoteTLSCallbackInjection/main.c#L56)) with runtime-retrieved values. This shellcode is responsible for restoring both original bytes and memory permission of the TLS callback function's address. 5. Inject both shellcodes: `g_FixedShellcode` and the main payload. 6. Patch the TLS callback function's address and replace it with the address of our injected payload. 7. Resume process. The `g_FixedShellcode` shellcode will then make sure that the main payload executes only once by restoring the original TLS callback's original address before calling the main payload. A TLS callback can execute multiple times across the lifespan of a process, therefore it is important to control the number of times the payload is triggered by restoring the original code path execution to the original TLS callback function. ### Demo The following image shows our implementation, `RemoteTLSCallbackInjection.exe`, spawning a `cmd.exe` as its main payload. <img width="1200px" alt="demo" src="https://github.com/Maldev-Academy/RemoteTLSCallbackInjection/assets/111295429/1b1b2c9c-17af-490c-8d77-ea11f53ccfaf"> ", Assign "at most 3 tags" to the expected json: {"id":"7199","tags":[]} "only from the tags list I provide: [{"id":77,"name":"3d"},{"id":89,"name":"agent"},{"id":17,"name":"ai"},{"id":54,"name":"algorithm"},{"id":24,"name":"api"},{"id":44,"name":"authentication"},{"id":3,"name":"aws"},{"id":27,"name":"backend"},{"id":60,"name":"benchmark"},{"id":72,"name":"best-practices"},{"id":39,"name":"bitcoin"},{"id":37,"name":"blockchain"},{"id":1,"name":"blog"},{"id":45,"name":"bundler"},{"id":58,"name":"cache"},{"id":21,"name":"chat"},{"id":49,"name":"cicd"},{"id":4,"name":"cli"},{"id":64,"name":"cloud-native"},{"id":48,"name":"cms"},{"id":61,"name":"compiler"},{"id":68,"name":"containerization"},{"id":92,"name":"crm"},{"id":34,"name":"data"},{"id":47,"name":"database"},{"id":8,"name":"declarative-gui "},{"id":9,"name":"deploy-tool"},{"id":53,"name":"desktop-app"},{"id":6,"name":"dev-exp-lib"},{"id":59,"name":"dev-tool"},{"id":13,"name":"ecommerce"},{"id":26,"name":"editor"},{"id":66,"name":"emulator"},{"id":62,"name":"filesystem"},{"id":80,"name":"finance"},{"id":15,"name":"firmware"},{"id":73,"name":"for-fun"},{"id":2,"name":"framework"},{"id":11,"name":"frontend"},{"id":22,"name":"game"},{"id":81,"name":"game-engine "},{"id":23,"name":"graphql"},{"id":84,"name":"gui"},{"id":91,"name":"http"},{"id":5,"name":"http-client"},{"id":51,"name":"iac"},{"id":30,"name":"ide"},{"id":78,"name":"iot"},{"id":40,"name":"json"},{"id":83,"name":"julian"},{"id":38,"name":"k8s"},{"id":31,"name":"language"},{"id":10,"name":"learning-resource"},{"id":33,"name":"lib"},{"id":41,"name":"linter"},{"id":28,"name":"lms"},{"id":16,"name":"logging"},{"id":76,"name":"low-code"},{"id":90,"name":"message-queue"},{"id":42,"name":"mobile-app"},{"id":18,"name":"monitoring"},{"id":36,"name":"networking"},{"id":7,"name":"node-version"},{"id":55,"name":"nosql"},{"id":57,"name":"observability"},{"id":46,"name":"orm"},{"id":52,"name":"os"},{"id":14,"name":"parser"},{"id":74,"name":"react"},{"id":82,"name":"real-time"},{"id":56,"name":"robot"},{"id":65,"name":"runtime"},{"id":32,"name":"sdk"},{"id":71,"name":"search"},{"id":63,"name":"secrets"},{"id":25,"name":"security"},{"id":85,"name":"server"},{"id":86,"name":"serverless"},{"id":70,"name":"storage"},{"id":75,"name":"system-design"},{"id":79,"name":"terminal"},{"id":29,"name":"testing"},{"id":12,"name":"ui"},{"id":50,"name":"ux"},{"id":88,"name":"video"},{"id":20,"name":"web-app"},{"id":35,"name":"web-server"},{"id":43,"name":"webassembly"},{"id":69,"name":"workflow"},{"id":87,"name":"yaml"}]" returns me the "expected json"