In this diary, I’ll show you a practical example of how steganography is used to hide payloads (or other suspicious data) from security tools and Security Analysts’ eyes. Steganography can be defined like this: It is the art and science of concealing a secret message, file, or image within an ordinary-looking carrier—such as a digital photograph, audio clip, or text—so that the very existence of the hidden data is undetectable to casual observers (read: security people). Many online implementations of basic steganography allow you to embed a message (a string) into a picture[1].

In the last week I ran into some issues that I hadn't anticipated:

While the old adage stating that “the human factor is the weakest link in the cyber security chain” will undoubtedly stay relevant in the near (and possibly far) future, the truth is that the tech industry could – and should – help alleviate the problem significantly more than it does today.

[This is a Guest Diary by Jacob Claycamp, an ISC intern as part of the SANS.edu BACS program]

If Attackers can abuse free online services, they will do for sure! Why spend time to deploy a C2 infrastructure if you have plenty of ways to use "official" services. Not only, they don't cost any money but the traffic can be hidden in the normal traffic; making them more difficult to detect. A very popular one was anonfiles[.]com. It was so abused that they closed in 2023![1]. A funny fact is that I still see lot of malicious scripts that refer to this domain. Of course, alternatives popped up here and there, like anonfile[.]la[2].

As promised in diary entry "XORsearch: Searching With Regexes", I will outline another method to search with xorsearch and regexes.

Obfuscation is very important for many developers. They may protect their code for multiple reasons like copyright, anti-cheat (games), or to protect their code from being reused. If an obfuscated program does not mean automatically that it is malicious, it’s often a good sign. For malware developers, obfuscation helps bypass many static security controls and slows down the reverse analysis process.

This month, Microsoft has released patches addressing a total of 125 vulnerabilities. Among these, 11 are classified as critical, highlighting the potential for significant impact if exploited. Notably, one vulnerability is currently being exploited in the wild, underscoring the importance of timely updates. While no vulnerabilities were disclosed prior to this patch release, the comprehensive updates aim to fortify systems against a range of threats, including remote code execution and privilege escalation. Users are encouraged to apply these patches promptly to enhance their security posture.