Questions tagged [javascript]
JavaScript or JS is an interpreted computer programming language. It was originally implemented as part of web browsers.
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frida-example-agent npm run build not correct
I git clone frida-example-agent and run npm install and npm run build, but the output is wired, like below
📦
928 /agent/index.js.map
578 /agent/index.js
215 /agent/logger.js.map
58 /agent/logger.js
✄
...
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Javascript: Compare Control Flow (to evade anti-debug and anti-tamper traps)
When reverse engineering obfuscated javascript, it may be protected by anti-tamper mechanisms.
I have a script which will work when run untouched, but cause a fatal javascript error when run in node ...
- 143
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How does google.com detect I'm in Firefox when already using Chrome's user agent
It's well known that google.com doesn't show the microphone search icon in Firefox, probably to incentivize people to use their web browser. (They give it on youtube.com, which is weird for being ...
- 131
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Yelp: getting documentId for certain operationName
Going through devtools activity for this page (reproducible for any Yelp business page), there's a reference to a GetReviewSummary GraphQL operation in a javascript file. This data shows up in the ...
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HTML/JS app - getting a reference to an element which is not part of the DOM
I am trying to debug an app which I don't own which uses HTML5 and JS, which displays a video stream. The issue is that the video stutters when viewed in high resolution.
Note that the code is ...
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Access a XREFs with frida
I have a string which has a XREF to a func. This func changes of address at every updates of the app I am working on. So this string is the only "stable" point I can rely on to access to ...
- 51
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frida hook `loc_*` or `sub_*`
Is it possible to hook a sub_... object in Frida ? I disassembled an arm64 executable, when running the app on my iPhone, I can see a lot of classes also in the disassembled executable, but I can't ...
- 51
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Generating specific request cookies for a website
I have a script that autocheckouts products on a website (bot), recently the site seemed to update something and I keep getting 403 blocks(Perimeter X). My old solution was simply to rotate and brute ...
- 21
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How to see the src of a Node.exe
Long story short, my friend sent me some scripts a while ago and lost a lot of his old source code and I wanted to see how it works but it's compiled into a node.exe (Node.js: Server-side JavaScript). ...
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Decompiling an executable compiled by vercel/pkg
I have a .exe file that I am trying to get the source code of, After some digging I figured out that it's in node.js and was compiled using vercel/pkg
I tried using pkg-unpacker however the output is ...
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De-Obfuscating/unminifying a JS code [not duplicate]
I have come across a lot of similar questions on the same heading but unfortunately, none of them provided me with the intended results.
I have a piece of code which, initially I am trying to ...
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Does anyone recognize this jQuery website plugin?
I am working on a site that was made years ago (not be me) and I need to identify a jQuery file manager plugin. This plugin shows a file manager view in a browser and allows the user to visually ...
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Frida hook InsertMenuItemW
I'm trying to get information about menu items in an application. Experimentally established that InsertMenuItemW is called. Thanks to the documentation, I set the number of input parameters and wrote ...
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'... Debugger undefined or null reference' error when WinDBG TTD Scripting with Javascript
I tried Javascript scripting on WinDbg (TTD specifically); but even in simple example I get error
Unable to get property 'Debugger' of undefined or null reference.
Line was simply var ctl = host....
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How does one go about reverse-engineering obfuscated/minified JavaScript in a browser like you would code in an IDE?
I am trying to figure out how some minified and possible highly-obfuscated JavaScript works. There are thousands of lines spanning multiple JS files. I have had a lot of success debugging it in my ...
- 111
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Bypass Javascript Debug Prevention in Firefox
I've looked around, and can't find an answer for my specific question. The closest I could find was this.
I'm trying to reverse engineer some suspicious Javascript, but it repeatedly calls a debugger ...
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Any good places to learn about JS de-obfuscation?
I am trying to make a bot on a specific website, so I have to reverse a lot of JS scripts. The reversing it self is not that hard but the de-obfuscation is. Lots of the scripts are obfuscated with ...
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How to clean obfuscated code from fake if statements?
I am trying to deobfuscate javascript code. Firstly I extracted strings from big array. Then I saw many parts like this
There is only one line of code which makes sense. Is there any Node.js cleaner ...
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Confusion about if statement in disassembly
I recently got into reverse engineering applications for fun. Can someone please help me with this if statement.
140005914 75 38 JNZ LAB_14000594e
140005916 48 8b 4 MOV ...
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Disassembly a win Linux file
I have a file that has a compiled assembly code and being loaded into javascript code for execution.
How can I “inspect” the file? I am aware of tools like immunity debugger or ollydbg but I am not ...
Badddy
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173
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Is there a tool to compare javascript files for differences, while also ignoring local identifier changes?
When trying to compare the difference between two minified javascript files with random identifier names, about 95% of the changes are identifiers being renamed. I would like to use a tool that ...
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Methods to alert inappropriate use of JS code
Let's say we have a JS code library that is not for sale, just internal. Of course, anyone who can access the website will be able to download that and reuse it.
To avoid others to reuse that library, ...
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automatically find the object "this" refers to in js
Im quite new to javascript and sometimes I find it really hard to find what object a keyword 'this' refers to. Is there a code editor that is able to do that for me? Or any other advice that could ...
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How can I modify or decompile Hermes JS bytecode?
Since React Native 0.60.4 developers can opt-in to use the Hermes JS Engine. This generates an index.android.bundle binary that contains Hermes JS bytecode.
The Hermes documentation mentions hbcdump ...
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244
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Where to start with reversing a custom JavaScript VM?
I have recently ran into the most heavy JavaScript obfuscation I've seen. It is using a custom VM to execute bytecodes. I have never dealt with such obfuscation, and I am wondering where I can start ...
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What browser do during initial web page request?
I am trying to understand why if I do fetch() 4 times on the active web page, after the fifth fetch server returns response that I am a "robot"
I am using google chrome
I go the following ...
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425
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How to get video file URL from Twitter
I am looking how to find the video URL of a Twitter video so I can code a converter later (using nodejs or something), but I can't figure out how to do this. I saw this but it doesn't really clear ...
- 121
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199
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How to locate the function being applied on password
I am thinking of taking up ethical hacking as a hobby. So, I installed Burp Suite Community Edition and set it up with Firefox. I opened Instagram and tried to login with these details (just for ...
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Load a *.dylib or *.so object into the Javascript V8 runtime?
I was reading this Frida release page and noticed it made the following reference:
Short of writing the whole agent in C, one could go ahead and build a
native library, and load it using Module....
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165
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Intercepting packets from Electron App to keyboard in Linux
I have a USB keyboard which has an Electron app to set the macros on the keyboard. I unpacked the app.asar file, and the JS files seem to indicate that it is a ReactJS app, and is a minified ...
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Trying to replicate encryption of an android app
I was trying to replicate/copy the encryption of an android app which uses CryptoJS with sha256 encryption as having seen in the source code of the android app. fingerprinting the app, it was built ...
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540
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Reverse Engineering Javascript - Out of Memory
I found this javascript file on one of those online movie streaming services and was interested in finding out what it does. However, after trying many deobfuscators I am still stuck. A major ...
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331
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How to modify JS with mitmproxy?
I am trying to reverse engineer a heavily obfuscated web application, and I would like to modify the JS to add logging. So far, I've set up mitmproxy, but I can't figure out what the best way to edit ...
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De-obfuscate JS code [closed]
I came across a script that converts font files from one type to another (i.e. WOFF to TTF, etc).
I would like to understand it and incorporate some of the code into a personal project. The script ...
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Is it possible to completely reverse this code?
i have this code i'm trying to deobfuscate
https://pastebin.com/g5mHpWE4
I used
https://beautifier.io/ and
http://www.jsnice.org/
but the result is still not good, current code:
https://pastebin.com/...
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How can I deobfuscate this javascript code
I am trying to deobfuscate this javascript code, but I don't know how it was created. Can you please tell me what the mechanism or the function is that generate such characters in javascript?
É=-~-~[]...
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How to hook eval function in node.js
As the eval() function of JavaScript is an evil, I want to hook or monkey-patch eval() function of JavaScript in node.js. I want to intercept all arguments passed in eval() function. Please guide me ...
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What's wrong with my mitm to support rr commands with gdbserver on IDA?
First of here is the gdb remote protocol doc.
The idea of the below script is the following - you enter an actual command (one that will be send as a direct packet see packets) in the gdb window then ...
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Need help reversing .m4t TTML subtitles format
I am currently trying to create subtitles for some proprietary Sony software. Unfortunatly, it only recognizes Sony's own .m4t subtitles format. After some research I found that this subtitles is also ...
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Decrypt config.bin file from Huawei B5328 router. I have source files
I need some help in decrypting the file config.bin generated by the page backup_setting.html from Huawei B5328 router.
I have access to all files in the router, even the www files hosted on the www ...
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How to programmatically add HTML DOM breakpoints in chromium?
I've seen from this post about Chromium DevTools that there exists the possibility to add DOM breakpoints. Given that I've a full range of elements to monitor I was trying to find a way to ...
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De-obfuscating code ran through JScrambler 3x via Eval() functions
I am relatively new to JS and de-obfuscation in general and I am having difficulties reversing some complicated JS. I know the code itself is obsfucated via jscrambler 3-4x and therefore is ran ...
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deobfuscating/decompiling extremely complicated javascript [closed]
I am working with some extremely complicated JavaScript. It is around 70,000 lines long and sections of the code look like this
U2xx.l11="0x78920d50";m2xx.r9G="11";b2xx.v3y="0x744ebc37";P2xx.K5h="...
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javascript hook comparisons
Look at this very basic javascript code:
if (s=='abcd')
{
if (s2='cdef')
{
...
}
}
I want to hook all tests: I want to get this:
(s,'==','abcd')
(s2,'==','cdef')
Is there a way ...
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WebSocket debugging in Javascript app gives "401 Unauthorized" [closed]
I'm attempting to reverse engineer a private API used by an Android app that makes use of WebSockets. These requests are made from JavaScript inside a WebView.
I use Charles to intercept both HTTP ...
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2
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4k
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How to copy video address from tweet?
Twitter has an option to right-click on a video and "copy video address" but this button seems to be broken as it doesn't copy anything to the clipboard, even after I disable Ghostery/adblock. I ...
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Is v8's --print-bytecode safe?
I just saw this post, and I was wondering if it's safe to get v8 bytecode in that fashion with --print-bytecode.
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Analyzing and deobfuscating complex JS code [duplicate]
I am looking to reverse engineer a very ugly piece of JS found here.
As far as I can tell, this script generates and sets some cookies on my browser that identify it on the site. Deobfuscating it ...
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1
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993
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How do you un-obfuscate JS code that is evaluating your browser environment?
Given this:
<script>var
_0x4c36=['w6rChcKeWsKXw7TCocOlNF8Kw7bCuMKdKsOWTMKjF2A=','V3PClhXDu8OCCMO5WwbCp8KhD8KVw7LDo8KOwr7CiA==','w6saBzVaIwbDk8OqHMKGwpvDgzzCixMTMMOL','...
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2
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How can a Javascript file drop .exe written in Visual Basic without network communication?
I am analyzing a malicious JS file, which is obfuscated in a way that I could not de-obfuscate. When I executed it in a virtual machine and spectated process changes, I noticed that a new executable ...
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