AI has been instrumental in the fight against cybercrime. Machine learning algorithms are far more adept at identifying suspicious emails and behaviors than human beings, which is why they are being deployed in security and monitoring software.
However, hackers have found a way of bypassing machine learning systems using cloaked emails, delivering phishing emails directly to corporate inboxes in order to infiltrate networks. This tactic is known as “Conversation Overflow” and you have to be prepared to face it head-on.
A Conversation Overflow attack is particularly insidious because it is designed to trick ML-powered cybersecurity tools into believing they are harmless and then categorizing them accordingly.
All systems that rely on AI and Machine Learning (ML) for email security are vulnerable to conversation overflow attacks. Many companies are adopting AI/ML based security solutions to analyze emails for phishing attempts, malware, and suspicious content. These are susceptible to being tricked by the hidden content in conversation overflow attacks.
Some advanced email client applications utilize AI to filter emails and prioritize your inbox. These can potentially be vulnerable if they depend solely on AI analysis without traditional security measures.
That is because Conversation Overflow attacks target the AI’s focus on analyzing the entire flow of conversation for legitimacy. The hidden content throws off the analysis and makes the attack email appear like a normal exchange.
While AI is making strides, current AI/ML models might not have the level of context understanding needed to differentiate between genuine conversation elements and the random hidden content used in the attack.
Each email consists of two parts: a section that is visible to the email recipient and a portion with hidden text.
The visible portion encourages the reader to complete an action, e.g., clicking on a link or entering their credentials.
The sections below contain strategically placed blank spaces that separate it from the hidden text, focusing on deviations from “known good” emails to trick the AI into believing it’s benign. This hidden text can be anything—gibberish, quotes, or even snippets of real conversations. The purpose is to make the AI/ML system see this extra content and classify the entire email as a normal exchange.
Because the AI used in cybersecurity communications analyzes patterns in email communications to pick up anomalies based on learnings from a database of “known bad” signatures, mimicking legitimate communication means the attack attempt goes undetected.
If the Conversation Overflow attack manages to breach defenses, the hackers will become even more adept at creating legitimate-looking messages. Hackers then exploit this trust by potentially sending further emails within the same conversation thread, urging you to click links or enter sensitive information, or by requesting credential reauthentication or personal information that can be sold online.
As more and more businesses adapt and adopt AI and ML technology, so do cybercriminals.
Combating conversation overflow attacks requires a multi-layered approach: combining the latest advances in tech with user awareness.
Security teams should constantly update and improve the AI and ML models used in email security systems. This can involve training the models on a wider range of attack scenarios, including those that utilize conversation overflow tactics. Additionally, incorporating advanced techniques like anomaly detection can help identify deviations from normal email patterns.
Sole reliance on AI/ML is not a foolproof strategy. A robust defense system should combine AI analysis with traditional security measures like keyword filtering, sender reputation checks, and URL sandboxing. This layered approach provides a stronger defense against various attack vectors.
Security software vendors regularly update their products to address new threats and vulnerabilities. It’s essential to keep email security software and applications updated with the latest patches to benefit from the latest security enhancements.
Security teams should stay informed about evolving cyber threats by subscribing to threat intelligence feeds. This allows them to adapt their tactics based on the latest trends and threats.
While AI and ML play an increasingly important role in cybersecurity, human expertise remains vital. Security analysts need to analyze data, identify trends, and configure security systems to effectively counter emerging threats. Combining human cybersecurity expertise with advanced AI can create a powerful defense.
Security solutions need to move beyond simply identifying malicious content and instead focus on detecting deceptive tactics. This could involve advanced analysis techniques that can identify inconsistencies in email structure, language patterns, and sender behavior.
Cybersecurity is a global challenge. Collaboration between security vendors, researchers, and government agencies is crucial to share threat intelligence and develop effective defense strategies. By working together, the security community can stay ahead of attackers and protect users from evolving threats.
Educating users about conversation overflow attacks and other email security threats is crucial. By understanding these tactics, users can be more vigilant when encountering suspicious emails. Training should emphasize critical thinking skills when evaluating email content, verifying sender legitimacy, and avoiding clicking on unsolicited links or attachments.
Make your employees aware of the rise of Conversation Overflow tactics. If they spot any hidden text, emails containing gibberish, or suspicious emails, they should be flagged immediately by the relevant support staff members. Make sure everyone knows the protocols and the process for flagging emails.
Conversation overflow attacks represent a wake-up call for the cybersecurity industry. While AI and ML offer significant benefits for email security, they are not a silver bullet. A layered defense approach that combines advanced technology with user awareness training is essential to combat these evolving threats.
Don’t shy away from AI: adapt. Make sure that you stay on top of the latest threats, and that you combine your own cybersecurity expertise (or that of your vendors) with the latest in technology.
Remember, there is no moment of “arrival” when it comes to cybersecurity defenses. It’s a constantly evolving process that requires vigilance, collaboration, and shared learning with the community.
Hackers are always adapting… make sure that you partner with cybersecurity experts who do the same.