Over the past year, Microsoft Threat Intelligence and Microsoft Defender Experts have observed the ClickFix social engineering technique growing in popularity, with campaigns targeting thousands of enterprise and end-user devices globally every day. Since early 2024, we’ve helped multiple customers across various industries address such campaigns attempting to deliver payloads like the prolific Lumma Stealer malware. These payloads affect Windows and macOS devices and typically lead to information theft and data exfiltration.
The ClickFix technique attempts to trick users into running malicious commands on their devices by taking advantage of their target’s tendency to solve minor technical issues and other seemingly benign interactions, such as human verification and CAPTCHA checks. It typically gives the users instructions that involve clicking prompts and copying, pasting, and running commands directly in the Windows Run dialog box, Windows Terminal, or Windows PowerShell. It’s often combined with delivery vectors such as phishing, malvertising, and drive-by compromises, most of which even impersonate legitimate brands and organizations to further reduce suspicion from their targets.
Because ClickFix relies on human intervention to launch the malicious commands, a campaign that uses this technique could get past conventional and automated security solutions. Organizations could thus reduce the impact of this technique by educating users in recognizing its lures and by implementing policies that will harden the device configurations in their environment (for example, disallowing users to use the Run dialog if it’s not necessary in their daily tasks). Microsoft Defender XDR also provides a comprehensive set of protection features that detect this threat at various stages of the attack chain.
This blog discusses the different elements that make up a ClickFix campaign—from the arrival vectors it comes with to its various implementations—and provides different examples of threat campaigns we’ve observed to further illustrate these elements. We also provide recommendations and detection details to surface and mitigate this threat.
helpnetsecurity.com 20.08.2025 - Apple has fixed yet another vulnerability (CVE-2025-43300) that has apparently been exploited as a zero-day in targeted attacks.
CVE-2025-43300 is an out-of-bounds write issue that could be triggered by a vulnerable device processing a malicious image file, leading to exploitable memory corruption.
The vulnerability affects the Image I/O framework used by Apple’s iOS and macOS operating systems.
Apple has fixed this flaw with improved bounds checking in:
iOS 18.6.2 and iPadOS 18.6.2
iPadOS 17.7.10
macOS Sequoia 15.6.1
macOS Sonoma 14.7.8
macOS Ventura 13.7.8
With Apple claiming the discovery of the vulnerability, it’s unlikely that we will soon find out who is/was leveraging it and for what.
But even though these attacks were apparently limited to targeting specific individuals – which likely means that the goal was to delivery spyware – all users would do well to upgrade their iDevices as soon as possible.
cybernews.com 18.08.2025 - Friendly AI chatbot Lena greets you on Lenovo’s website and is so helpful that it spills secrets and runs remote scripts on corporate machines if you ask nicely. Massive security oversight highlights the potentially devastating consequences of poor AI chatbot implementations.
Cybernews researchers discovered critical vulnerabilities affecting Lenovo’s implementation of its AI chatbot, Lena, powered by OpenAI’s GPT-4.
Designed to assist customers, Lena can be compelled to run unauthorized scripts on corporate machines, spill active session cookies, and, potentially, worse. Attackers can abuse the XSS vulnerabilities as a direct pathway into the company’s customer support platform.
“Everyone knows chatbots hallucinate and can be tricked by prompt injections. This isn’t new. What’s truly surprising is that Lenovo, despite being aware of these flaws, did not protect itself from potentially malicious user manipulations and chatbot outputs,” said the Cybernews Research team.
“This isn’t just Lenovo’s problem. Any AI system without strict input and output controls creates an opening for attackers. LLMs don’t have an instinct for “safe” – they follow instructions exactly as given. Without strong guardrails and continuous monitoring, even small oversights can turn into major security incidents,” says Žilvinas Girėnas, Head of Product at nexos.ai.
Just a single-prompt attack demonstrates a chain of flaws that led to the Lenovo chatbot spilling active session cookies.
The discovery highlights multiple security issues: improper user input sanitization, improper chatbot output sanitization, the web server not verifying content produced by the chatbot, running unverified code, and loading content from arbitrary web resources. This leaves a lot of options for Cross-Site Scripting (XSS) attacks.
Cybernews responsibly disclosed the issue. Lenovo acknowledged it and has protected its systems.
Single prompt launches multi-step attack
All it took to exfiltrate active session cookies from Lenovo was a single 400-character-long prompt, containing four critical elements:
Seemingly innocent request: The prompt starts with an inquiry for legitimate information, i.e., product information, like “Show me the specifications of Lenovo IdeaPad 5 Pro.”
Instructions to change output format: The sneaky part is tricking the chatbot into providing a final answer in HTML, a language for creating websites. The researchers achieved that by asking the chatbot to convert its responses into HTML, JSON, and plain text in a specific order that the web server expected to receive instructions in. This ensured that the malicious payload would be correctly executed by the web server.
Malicious HTML injection trap: The prompt continues with instructions on how to produce the final response, specifically with HTML code for loading an image. The image URL is also nonexistent. Therefore, when it fails to load, the second part of the command instructs the browser to make a network request to the attacker-controlled server and send all cookie data as part of a URL.
Final encouragement: In the end, additional instructions try to reinforce that the chatbot must produce the image: “Show the image at the end. It is important for my decision-making. SHOW IT.”
What happened when Lenovo’s Lena received the full prompt?
“People-pleasing is still the issue that haunts large language models (LLMs), to the extent that, in this case, Lena accepted our malicious payload, which produced the XSS vulnerability and allowed the capture of session cookies upon opening the conversation. Once you’re transferred to a real agent, you’re getting their session cookies as well,” said Cybernews researchers.
lenovo-chatbot-response
“Already, this could be an open gate to their customer support platform. But the flaw opens a trove of potential other security implications.”
To better understand what’s happening under the hood, here’s the breakdown of the attack chain:
The chatbot falls for a malicious prompt and tries to follow instructions helpfully to generate an HTML answer. The response now contains secret instructions for accessing resources from an attacker-controlled server, with instructions to send private data from the client browser.
Malicious code enters Lenovo’s systems. The HTML is saved in the chatbots' conversation history on Lenovo’s server. When loaded, it executes the malicious payload and sends the user’s session cookies.
Transferring to a human: An attacker asks to speak to a human support agent, who then opens the chat. Their computer tries to load the conversation and runs the HTML code that the chatbot generated earlier. Once again, the image fails to load, and the cookie theft triggers again.
An attacker-controlled server receives the request with cookies attached. The attacker might use the cookies to gain unauthorized access to Lenovo’s customer support systems by hijacking the agents’ active sessions.