From ee85e328d758f66c5dba2f640739f1661b8efde8 Mon Sep 17 00:00:00 2001 From: Daksh Dadhania <63968989+DakshDadhania@users.noreply.github.com> Date: Tue, 20 Feb 2024 23:05:15 +0530 Subject: [PATCH] Delete BITSCTF-2024/Forensics/Covert-Communications.md --- .../Forensics/Covert-Communications.md | 21 ------------------- 1 file changed, 21 deletions(-) delete mode 100644 BITSCTF-2024/Forensics/Covert-Communications.md diff --git a/BITSCTF-2024/Forensics/Covert-Communications.md b/BITSCTF-2024/Forensics/Covert-Communications.md deleted file mode 100644 index 29c3f40..0000000 --- a/BITSCTF-2024/Forensics/Covert-Communications.md +++ /dev/null @@ -1,21 +0,0 @@ -## Covert Communications Challenge Solution Overview - -### Initial Analysis -Received a `.png` image and a `.wav` audio file. Initial examination of the `.wav` file's spectrogram revealed no secrets, but treating the audio as SSTV (Slow Scan Television) noise was suggested, leading to the discovery of another image. - -### Decoding the SSTV Image -Using an SSTV decoding tool, I converted the audio file into an image that contained a ZIP archive named `secret.zip,` which was password-protected. - -### Extracting the ZIP Archive -The password `mogambro` (found within the challenge context or possibly within the provided images) unlocked the ZIP archive, revealing two `.pkl` files: `enc_data.pkl` and `tempo.pkl`. - -### Deciphering the Message -The challenge hinted at using Huffman coding and histogram analysis to decode the hidden message. So, it was deduced that the `.png` image contained the encrypted message using steganography, specifically histogram shifting and Huffman coding. - -### Using External Resources -A GitHub repository ([TejveerSingh13/Image-Steganography](https://github.com/TejveerSingh13/Image-Steganography)) was found that matched the challenge's requirements. This repository demonstrated how to use Huffman coding and histogram shifting for steganography. - -### Decoding the Final Message -The hidden message encoded in the image was successfully extracted from the GitHub repository. - -The final flag was: `bitsctf{s73g4n06r4phy_15_n07_45_345y_45_17_533m5}`.