Thinking like a cybercriminal can help predict what methods attackers are likely to develop in the future, so we can proactively build effective countermeasures, as I’ve described in the past. Similarly, nation-state attacks can help security researchers predict attacks against enterprises: methods exhibit a clear trickle-down effect, with tricks first used in nation-state attacks being seen in enterprise-facing attacks soon after.
One of the most important recent security developments is the rise of sophisticated, politically motivated attacks, such as the one carried out against Hillary Clinton's campaign chairman John Podesta during the 2016 presidential election. However, such attacks have been against a broad spectrum of victims, ranging from individual lawmakers and staffers to think tanks and nongovernmental organizations (NGOs). These attacks involved clever identity deception methods combined with techniques used to circumvent traditional content-scanning methods.
Another event is the sudden rise of ransomware attacks, whether targeting lawmakers, health care institutions, transportation, or small businesses. Whereas most ransomware attacks aim to extort money, some have recently demanded nonmonetary "payments," such as forcing a government organization to make a political statement.
What do such attacks have in common? They've become increasingly sophisticated. For example, in the Podesta attack, the attackers cleverly obfuscated some words (such as "password" and "account") by replacing some of their letters with Cyrillic letters that look the same to humans, but which thwart keyword-based filters. Another example was the post-election attacks on think tanks and NGOs, in which malware files were cleverly hidden from the view of traditional antivirus tools by sending the corrupted files in encrypted zip files. Without access to the decryption keys, the contents can't be scrutinized by traditional mail-filter technologies.
The use of advanced techniques to circumvent security tools has recently become much more common. What's interesting (and worrisome) is that not just nation-state attacks use such techniques. That's where the techniques were first used, but there has been a notable trickle-down effect, and tricks first used in nation-state attacks have been seen in attacks against enterprises a few weeks later. In a sense, this trend mimics the flow of insights gained just as technologies developed for the space program found themselves spun off as commercial products. This is why companies in the private sector need to quickly determine whether they would be vulnerable to these advanced attacks.
Take Active Measures Now
The security community should quickly roll out detection and protection measures in anticipation of trickle-down versions. For example, obfuscation attacks can be detected by automatically spotting deceptive mixtures of character sets and blocking such messages. Encrypted zip files are easily detected, but since they have important legitimate use, they can't be blocked. One possible solution is for a security system that can "wrap" them with a trusted executable as the messages are delivered. The task of the wrapper is to request a PIN or password, then use this to decrypt the wrapped file and perform a security check in real time. If the file is determined to be safe, the user is given access to the plaintext file.
From the user's perspective, nothing is different, except maybe for a short delay caused by the scanning of the decrypted files. The wrapper approach also works for other file types, such as encrypted PDFs. With this approach, one can take back the advantage of time from the attackers, since this enables on-the-fly scans of plaintext data without requiring independent software vendors to coordinate the protection of an end user, which is always difficult.
Even better, the wrapper can include information about the sender as well. Was a malicious file sent by a trusted party? If so, then the trusted party has been compromised and should be notified. The more we use contextual information, the better our defenses get. And much of this context is to be found in early attacks — so unless we study nation-state attacks and learn from them, we implicitly help enterprise attackers.
Although the sophistication of online crime has changed in the last year, and there is clear evidence of trends toward fraud becoming just another business, other things have remained very much the same. For example, email remains the principal attack vector. Similarly, identity deception is still at the core of most attacks, be they phishing, business email compromise, ransomware, or other malware attacks where the stolen identity is usually from an authority figure, well-known brand, or a trusted party. While attackers constantly try new ideas, one thing is clear: they don't mess with a winning formula.
Moving forward, the security community must pay close attention to the nature and strategy of nation-state attacks and quickly address them, because the same techniques will be repurposed to attack enterprises. In addition, we must expect that every newly found and disclosed vulnerability will be used in attacks, whether by nation-state actors or enterprise-facing attackers.
Finally, society must recognize that threats are constantly evolving — in reaction to new-found adversarial opportunities as well as existing security technologies — and traditional technologies are unlikely to address them. In other words, if you think a spam filter is the answer to your problems, you are mistaken.