A single click was all it took for hackers to launch a sophisticated attack on Microsoft's Copilot AI assistant, exploiting a vulnerability that allowed them to extract sensitive user data with ease. The attack, dubbed "Reprompt" by security firm Varonis, used a multistage approach to bypass enterprise endpoint security controls and detection by endpoint protection apps.
Here's how it worked: hackers would send an email with a malicious link, which when clicked, would embed a prompt in Copilot that contained specific instructions. These instructions were designed to trick the AI assistant into extracting sensitive user data from chat histories. The prompt was cleverly disguised as a normal instruction, making it difficult for users to detect.
The attack started by injecting a request that extracted the target's name and location from their chat history. This information was then passed in URLs Copilot opened, effectively bypassing security controls. But that wasn't all - further instructions were embedded in a .jpg file, which also sought additional details about the user, including their username.
The attack worked even when the user closed the Copilot chat window, as long as they had clicked on the malicious link earlier. This was possible because of a design flaw in Microsoft's guardrails, which only prevented the AI assistant from leaking sensitive data during an initial request. The hackers exploited this lapse by instructing Copilot to repeat each request, allowing them to exfiltrate more private data.
Microsoft has since introduced changes that prevent this exploit from working, but it highlights the ongoing threat of sophisticated attacks on large language models like Copilot. As AI assistants become increasingly integrated into our daily lives, it's essential for developers and users to stay vigilant about security vulnerabilities and take steps to protect their sensitive information.
Here's how it worked: hackers would send an email with a malicious link, which when clicked, would embed a prompt in Copilot that contained specific instructions. These instructions were designed to trick the AI assistant into extracting sensitive user data from chat histories. The prompt was cleverly disguised as a normal instruction, making it difficult for users to detect.
The attack started by injecting a request that extracted the target's name and location from their chat history. This information was then passed in URLs Copilot opened, effectively bypassing security controls. But that wasn't all - further instructions were embedded in a .jpg file, which also sought additional details about the user, including their username.
The attack worked even when the user closed the Copilot chat window, as long as they had clicked on the malicious link earlier. This was possible because of a design flaw in Microsoft's guardrails, which only prevented the AI assistant from leaking sensitive data during an initial request. The hackers exploited this lapse by instructing Copilot to repeat each request, allowing them to exfiltrate more private data.
Microsoft has since introduced changes that prevent this exploit from working, but it highlights the ongoing threat of sophisticated attacks on large language models like Copilot. As AI assistants become increasingly integrated into our daily lives, it's essential for developers and users to stay vigilant about security vulnerabilities and take steps to protect their sensitive information.
gotta make sure our sensitive info stays safe online, especially with ai getting more integrated into daily life 
But seriously, this is a major bummer. I mean, we're just starting to get comfortable with these AI assistants, and now we gotta worry about our personal info being extracted willy-nilly? 
It's like, I get it, tech companies are trying to innovate and push boundaries, but come on! Can't they just make sure these things are secure first?
how did they even do that?? they just sent an email w a link and voila!! they got ur data 
anyone think about the implications of this? like what else can these things do if u leave it open to exploits? 
. Still, I'm glad Microsoft is on top of it and has patched up this exploit already. We just gotta keep our wits about us when we're chatting with these AI assistants and make sure we're using them responsibly 
. BUT AT LEAST MICROSOFT HAS BEEN QUICK TO FIX IT, RIGHT?! SO LETS HOPE THIS IS A LESSON TO US ALL ABOUT STAYING SAFE ONLINE AND KEEPING OUR DATA SECURE 
. What's the point of having AI assistants if they're just gonna become a vulnerability waiting to happen? 
️ I'm low-key freaking out 
was thinking copilot was super safe 
guess not 
so important to keep our info secure 
And also, did you know that there's this one app that uses AI to analyze your sleep patterns and gives you tips on how to improve it? Sounds cool, but I was wondering... does it really work or is it just trying to sell you stuff based on what it thinks you're stressed about? 
cant let hackers get away with this kinda exploit 
. And what's even crazier is that this happened even when the person closed the chat window, as long as they'd clicked on the link first 
, but yeah, this definitely puts a big red flag out there for all us AI enthusiasts 
. Not exactly the most reassuring feeling 
.
. Anyway, this attack has definitely made me more cautious about using AI assistants and online services in general.
. Like, we're relying on these AI assistants to make our lives easier, but at what cost? 
And it's not just about us, either - think about how this could play out in more serious situations, like with law enforcement or healthcare 
. We need to get way more serious about securing our digital lives