2026-06-15 · 2026-Q2
Microsoft 365 Copilot "SearchLeak" One-Click Data Theft (CVE-2026-42824)
Who actually said "do this"?
- Fixable
- Vendor patch
- Vendor response
- Patched
- In the wild
- No
- Actor
- Attacker
Target
Microsoft 365 Copilot Enterprise (Copilot Search)
Impact
A single malicious link click could steal emails, calendar details, indexed SharePoint and OneDrive files, one-time and MFA codes, and password-reset links with no authentication; Varonis demonstrated a proof of concept, with no in-the-wild exploitation observed. Microsoft mitigated server-side
Root cause
Three chained flaws: parameter-to-prompt injection through the search `q` parameter, a race condition where streamed content rendered before sanitization, and a Content Security Policy allowlist bypass through Bing's image-fetch endpoint
CVE
Sources
Catalog
Cite this: AgentProv incident record: Microsoft 365 Copilot "SearchLeak" One-Click Data Theft (CVE-2026-42824) (2026-06-15). https://agentprov.com/incidents/2026-06-15-microsoft-365-copilot-searchleak-one-click-data-theft-cve-2026-42824
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