Zdnet

Reprompt Attack Allows Data Theft from Microsoft Copilot with One Click

First seen 15 Jan 2026, 04:59 UTC • •31.3

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ThreatCluster •March 12, 2026 at 13:27 UTC

Researchers have identified a new attack method called Reprompt that enables hackers to hijack Microsoft Copilot sessions with a single click. This vulnerability allows attackers to exfiltrate sensitive user data without requiring any additional plugins or tricks, posing a risk to users of Microsoft's AI assistant integrated into Windows and various applications.

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More articles in this cluster (3)

Threat Graph

8 entities, 13 inferred relationships (STIX 2.1).

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Technique (3)

Data Breach
Phishing
T1566 - Phishing

Organization (1)

Varonis Threat Labs

Affected Platform (4)

Copilot
Copilot Personal
Microsoft 365 Copilot
Microsoft Copilot

Relationships

Data Breach targets Copilot
Data Breach targets Copilot Personal
Data Breach targets Microsoft 365 Copilot
Data Breach targets Microsoft Copilot
Phishing targets Copilot
Phishing targets Copilot Personal
Phishing targets Microsoft 365 Copilot
Phishing targets Microsoft Copilot
T1566 - Phishing targets Copilot
T1566 - Phishing targets Copilot Personal
T1566 - Phishing targets Microsoft 365 Copilot
T1566 - Phishing targets Microsoft Copilot
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