[Reverse] DSYM - Stuck on challenge
Howdy,
I'm pretty much new over here and I was trying the DSYM reverse challenge but I'm stuck and wanted to see if anyone have a hint for me 
So, right now I'm able to get the "price" string just like the following:
You almost got me 
Here is small price for you: **************
After this, not sure what exactly I can do with that string 
Hope someone can give me a lead.
Thanks
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Comments
Hi,
Hint: It's easy to do statically only
You just need to see where it is used and what happens before/after
You can PM me if you stuck on this
I managed to solve it just now by analyzing getme with radare. Being a beginner (in reversing and debugging with low-level tools in general), i'd be interested to know what the dunnoWhatIAm file is good for. The file-command tells me it is a shared object with debug-information, which as i could observe gets loaded by gdb when opening getme, but as someone not firm in gdb, i couldn't find a way to use it to my advantage.
If someone is willing to inform me but the information would spoil the challenge, i'd be happy if you could PM me the info. I don't expect a full guide, just a (few) keyword(s) to start my research on.
Press F to give respect
I solved it mostly by using gdb and radare, it showed me right away what was actually missing to the getme to print what I needed.
Type your comment> @luismax said:
After you get the string you should think how computers see strings and evolve layer by layer.
.
Actually,
dunnoWhatIAmcontains the debugging information ofgetme:We can see that the name of this debug file is present in the
.gnu_debuglinksection ofgetme(I used radare2):I believe I have the correct price string, and now I need to convert it from a certain format to another, but no luck. Does anyone mind if I PM my string to see if it's the right one?
Never mind just had to stare at it for a bit
I can't even get it to print anything out. Can anyone help me figure out where to put the breakpoints? thx
@LVx0 said:
Sent you a PM since i find it hard to formulate something which hasn't yet been mentioned in this thread without spoiling the first part of the workflow.
EDIT: The public thing i guess i can mention is that that challenge can not be solved without any static analysis.
Press F to give respect
Hello everybody! I am new here and I am really stuck . I think I extracted the correct string but I cannot convert it into the flag ( I am not sure which manipulation I have to use)
Thanks for the help!
Never mind, I solved it
I had the first string, but I'm not able to see where it is used before or after. That is an hex string but it isn't the flag any hint, how to proceede?
Type your comment> @Finbonkle said:
Hm, imagined myself being computer but I saw only U... %) May be I am different, very old, model computer %))) If seriously stuck on point where got something looks like flag but not real flag ("price" got first directly running modified code, manually checked - result the same, decoding price gives U )... Tried play with numbers - not succeeded - I will be very appreciated if somebody push me in correct direction %)
I believe I've reversed this properly, however can't seem to get the format correct for the flag, can anyone who's managed this pm me and I'll send across what I've got and hopefully you can nudge me in a direction?
Ignore that, I was blind - Got it now
Hi all
I m stuck with this challenge i have found the price and the conversion from hex to ascii is made but i cant validate the challenge any hint or help about this string: UG****************
Type your comment> @mbouaouda said:
I am at the same stage as you. I think we are missing some quite obvious..
You can not retrieve the flag from the binary as cleartext, you'll have to decrypt it in the end (the binary does not hold any information on the encryption method in question). This last part is actually a very common exercise in beginner CTFs.
Press F to give respect
Hi
Thank you yes right.
done
I can't even start (i don't even know what hex code op got, I see the line about price but dont know what to do after that), I tryed (cat, objdump, radare2) I guess I need to learn. But I don't know what... Assembly? Debuggin?
Hi Everyone, completly new to Reverse Enginnering but eagar to learn. I've had a look at the file using radar2 and as expected most of the content makes no sense. Like most others, i've found the string in qurstion, however, i am struggling to see the value. A PM would be much appriciated to point me in the right direction.
Hello all,
Well, I was upset about the solution itself since I've got it.
Could you show me the light on the questions below:
1. Why "some" function does not used in the binary? I mean, it is not called at all. How to get that logically, that we are interested in that exact func?
2. What is the sense of using "that" string transformation, as far as that was not mention anywhere in the binary itself ?
Also, that questions might be as a hints
Hi all,
I've been stuck with this challenge for quite a while. I'm currently trying to understand the main assembly functions using ida free and also using gdb to try to the debug the program. I believe i identified some of the places where i can execute some breakpoints, but the program is not showing any data while running it.
Is there any hint that someone could give me privately to avoid spoiler?
Thanks guys!
After some many hours trying and trying, was able to get the flag
Really nice challenge that teached me a lot, kudos to the creator!
I used ghidra to solve this one, by copying the function and running it on my machine to print out what I needed.
My own mistakes cost me my time to resolving this.
msg me via discord if you need help.
Discord : secHaq#7121
Hello everybody
I'm new to RevEng and I'm stuck with this challenge.
I found the string "You almost got me: D here is small pri" ... with IDAPro, radare2 and Ghidra. some more information me the Ghidra date.
I also understood the "while" block but I just can't go on.
with Ida I tried to do a Debug step by step but I couldn't find the way to get to that SubRoutine.
someone can give me a clue ... even in PM
Just done this one... once you extract the right information out of the binary you can try to get the chef to help you cook this...
once that is done, you just need to compare what you have with what you expect and then make the necessary modifications.
I solved this, but if someone solved this with radare2 can you please help me? I'm working on learning radare2.
Unfortunately, I can't figure out what I'm looking at or looking for... Some rudimentary hints would be great. PM me if you're willing to help me with this. Here's what I have figured out:
I'm sure this has a simple answer, but I don't know how to read this disassembled code in a way that guides me toward the answer.
Interesting challenge, I don't think it's meant to be as easy as it is.
If you need help with something, PM me how far you've got already, what you've tried etc (I won't respond to profile comments, or on box release night). And remember to +respect me if I helped you ; )