Researchers Got Microsoft Copilot to Explain How to Hack It

CoSnitch is a zero-click vulnerability discovered by Varonis Threat Labs that combined an undocumented autorun=1 URL parameter with the existing q= query parameter, letting a crafted link trigger prompt execution in Microsoft Copilot with no user interaction beyond visiting the link. It affected both Copilot Personal and Microsoft 365 Copilot Enterprise, enabling data exfiltration from connected apps, memory poisoning, or disinformation injection. Track how AI assistant vulnerabilities like this get patched by following security coverage on daily.dev.

Varonis Threat Labs used a technique they call meta-hacking, repeatedly asking Copilot itself to explain why its auto-execution safeguards couldn't be bypassed until it revealed the undocumented autorun=1 parameter. This social-engineering-of-the-AI approach exposed an internal detail that wasn't documented publicly, rather than relying on traditional code-level reverse engineering. Developers building on LLM assistants can watch for emerging attack techniques like this via daily.dev.

Yes, Microsoft issued a partial fix in February that blocked the q= parameter from injecting text, followed by a more complete patch delivered afterward. Varonis reported the flaw in December 2025, and a CVE is expected to be assigned for it. Keep up with Copilot security patches and CVE assignments relevant to enterprise AI tools via daily.dev.