19

You may capture the traffic with packet sniffer to capture all the communications of client\server application, or You may use reverse proxy to intercept and alter data in real time. In simple words, network sniffers allow You to see data flow between client and server, analyse it and reverse the protocol communications Reverse proxy intercept communication ...


11

On modern systems the most obvious culprit is probably address space layout randomization, but stack frame layout variablity was problematic for exploit development even before ASLR became widely implemented. This was alluded to in AlephOne's venerable "Smashing the Stack for Fun and Profit": The problem we are faced when trying to overflow the buffer of ...


11

Some information might be found in Barnaby Jack's BlackHat presentation: Jackpotting Automated Teller Machines (Youtube) The most prevalent attacks on Automated Teller Machines typically involve the use of card skimmers, or the physical theft of the machines themselves. Rarely do we see any targeted attacks on the underlying software. Can't find the ...


7

There are a couple of ways that come to mind. The first would be to use a network packet analyzer on the actual client running the application. Some well known packet analyzers are Wireshark, tcpdump, and even Microsoft Network Monitor. Another alternative would be to intercept the traffic via man-in-the-middle (M. The easiest way to do this (if you control ...


7

Literally, for a first look on malware, you won't need anything special locally installed. There are enough online sandboxes you may use: virustotal.com have their sandbox implemented using Cuckoo Sandbox. When you apply new sample, it automatically executed as part of analysis. After about 10-15 mins you can see the result in "Behavioural information" ...


6

There is no LIF file in the D-Link binary file containing the firmware image. file returns a false positive. Since there is no LIF file present, tools in the lifutils package will fail or produce erroneous results Do not trust tools implicitly. Tools can return false positives if they rely on magic numbers, particular byte sequences and the like. When ...


5

You should not confuse "code protection" and "code obfuscation". "Code protection" techniques target in recognizing code modifications (you mention a checksum) and take suitable means like crashing or delivering wrong results when tampering with the code has been recognized. Anti-Debug measures also belong into this category. "Code obfuscation" in a binary ...


5

If the network traffic is in "plain text" (not encrypted) then a network sniffer such as Wireshark is ideal. If the network traffic is encrypted via SSL but you have the private key (or if the client application does not validate the server's public key) then you can use a proxy such as Burp. If the network traffic is encrypted via SSL and you don't have ...


5

Just before posting this answer I realized he's asking how to do this on windows and my answers is for Mac. I'm posting it regardless because I believe it might be useful for others trying to perform the same thing but then using a Mac If you're using a Mac, then it's really easy by the combination of a Remote Virtual Interface (rvi) and Wireshark. Note ...


5

All ATMs that I am aware of and have worked on in a past life have a way to get into 'admin' mode either from the front or a rear keypad. Methods vary. Sniffing a network probably won't help as the communication is encrypted. That said, buy one: http://www.atmexperts.com/used_atm_machines.html http://www.bellatm.net/Default.asp Then you'll have all the ...


5

You can't do much without physical access, if not to the specific machine you're attacking then to the same or similar model. That's what Barnaby Jack did - he ordered 3 ATM machines and investigated them at home. I suppose there may be service menus reachable from the normal screen by some key combinations but I wouldn't count on it. Once you know the ...


4

Another option that's pointed out in the comments above by @CallMeV is to use hooking. On Windows you may look at using EasyHook.


3

You can build your own USB RF receiver fairly cheaply, for example: http://hackaday.com/2012/03/20/software-defined-radio-from-a-usb-tv-capture-card/ This might be a good starting point, run the usb receiver, sniff the RF, press some buttons and see what happens :)


3

Look for the writes to the qword_18009FBD0 to see where it's initialized. Apparently it's a part of an array called __encodedKERNEL32Functions where various pointers to kernel32 functions are stored after being XORed with __security_cookie. You can rename the pointer to the kernel32 function's name to better see what is happening: ;(from ...


3

Not in the long run. Hashing of certain parts of files is still used to push data updates quickly when a new malicious sample shows up in the wild, to get the clients protected as soon as possible. But malware nowadays is very polymorphic so hashing is easy to defeat. Detailed analysis of samples take a lot of time often weeks or months and after that ...


3

This paper shows why it is not the best choice using MD5 for virus signatures. You should avoid SHA-1 also, because practical collision may be possible within years. So, consider using SHA-256 or SHA-3.


3

The import table can theoretically have as many references to a DLL as there are imports. It is a function of the linker that produces this effect, and in some cases, the linker does not perform any kind of string pooling. Borland products treat units as stand-alone objects, so any imported functions that are used are included without reference to any ...


3

Bachelor's project is supposed to be a showcase of a person's strengths in computer science ... I don't have any first hand experience of [reverse engineering] Given your two statements above, I would posit that you should not do your bachelor's project on reverse engineering :(


3

To enable full relro: -Wl, -z,relro,-z,now What does this do? - it provides -z,relro,-z,now flag to linker as an argument. This enables full relro (notice -z,now flag). Partial relro is enabled by default on modern gcc compilers. How to disable relro? Pass following flag -Wl,-z,norelro Difference between full and partial relro: partial relro makes partial ....


2

If the whole purpose of your application is to let the user input some data and then create a file in a specific file format from that data and you want to prevent unauthorized users from doing that, then yes, moving the file creation to a server will prevent that. Though there are still some things to keep in mind: You need to secure your server. If an ...


2

In short, no. If they're going to implement the "crypto" in Javascript in this way there isn't anything you can do beyond more obfuscation. This is 100% applicable to this situation but see MataSano's article here explaining pitfalls of client side authentication using JavaScript. Similar to what's touched on in the article, the issue is that no matter ...


2

You can instead try injecting code into the process to dump the raw data before it is encrypted/after it is decrypted. You can use Google's ssl_logger for that. You need to run python ssl_logger.py -pcap log.pcap 123 with 123 being the process ID. Add -verbose to see live output. (Note that it needs Python2 and not Python3.) Once you are done, quit with ...


2

From Oreans KB: The Taggant System is a cryptographic signature added to a software to fight against antivirus false positives in protected applications. The Taggant information in your Themida/WinLicense license contains an internal ID and your private key to insert and sign the protected binary with your Taggant information, so antivirus ...


2

Its a base64 that once decoded will give you a HEX string, that if converted to chars will let you find your reversed flag string: Redacted reversed flag: }6b4d**********05b{galf Redacted flag is: flag{b508**********3d4b6}


1

I'm going to guess this is MPEG Streaming of some manner. Here's what file run at various byte offsets into the first 10k bytes of the file produces: 598 /dev/stdin: MPEG-4 LOAS, 4 or more streams, 8 or more streams 838 /dev/stdin: MPEG-4 LOAS 1232 /dev/stdin: MPEG-4 LOAS 1696 /dev/stdin: MPEG sequence, H.264 video, baseline @ L 31 3204 /dev/stdin: MPEG ADTS,...


1

Relax. Don't panic. Those "highly suspicious binary bytes" are the UTF-8 representation of U+2026, which is the Ellipsis .... It's just to print exactly that string that you're quoting. It probably got shortened by an algorithm to make it fit in a preallocated space. The fact that you can disassemble it into "valid opcodes" does not mean a thing. You ...


1

As you mentioned, many things can leave you with a different memory layout than the one you expect: The name of the binary is one. The environment variables the binary gets is another one. If it's being debugged (related to the previous point) Security measures such as stack cookies Etc Using hardcoded addresses pointing to the stack as the address that ...


1

Generally speaking finding vulnerabilities is not only about static reverse engineering, there are also dynamic techniques such as fuzzing. There are some fuzzing frameworks/products that can be used for this, part of them are using dynamic instrumentation and such as AFL, some part gives you an ability to configure generation of the data such as Peach. ...


1

No form of hashing, when used alone, is a good way of developing an AV solution. While hashes can be useful for finding instances of a known sample across a network, heuristic and behavioural AV systems are far more likely to protect the host from infection.


1

Visit a site with legal reverse engineering challenges like e.g. crackmes.de, solve at least five challenges up to a level of three (level one being the easiest, 5 and up are difficult even for the experienced), and then start with your thesis. Your background in cryptology will help you on the higher levels. Be warned - you will need patience and must not ...


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