The flag for this challenge is devided into two parts.
Finding the first part was as easy as just listening to the voice messgae (95cd605bea9065f44530).
The second part however was a bit more challenging. After checking the file in hex viewer, I found out that it was a mp4 video. So I decomposed the video frames and compared the two of the frames. It was obvious that it’s the same old stegano challenge they give every year (very creative!). So I merged all the images together to get the second part of the flag (cb13b6659dde).
ffmpeg -i LS.mp4 images/%d.png
cp images/1.png part2.png for f in `ls -v images`; do compare part2.png images/$f part2.png; done