This update of what-is-new-.py, my tool that reports what lines inside files are new (e.g., never seen before) has a new option: -a –action. It allows me to launch a command when something new is detected.
I use this for example to be alerted via TelegraM; More details in an upcoming blog post.
Here’s a new beta version of my tool pngdump.py, a tool to analyze PNG files.
I took a look at all files on MalwareBazaar with a PNG tag, and made updates to pngdump.py to handle them.
I found 3 types of “PNG” files.
First, files spoofing PNG files: files that are not PNG files, but have a .png extension.
Like .exe and .rar files:
Second, valid PNG files with an appended payload:
Third, invalid PNG files. For example, PNG files with the right record structure, but where the Zlib compressed image is replaced by an RC4 encrypted payload (IcedID):
I also have other samples, but that’s for another blog post.