CVE-2026-21520

HIGH

Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive information through network attack vector

CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Published: 1/22/2026Modified: 2/2/2026

Related Intelligence (1)

CRITICALData Breach

Copilot and Agentforce fall to form-based prompt injection tricks

Enterprise AI agents are supposed to streamline workflows. Instead, two fresh findings show they can just as easily streamline data exfiltration. Security researchers have uncovered prompt-injection vulnerabilities in both Microsoft Copilot Studio and Salesforce Agentforce that allow attackers to execute malicious instructions via seemingly harmless prompts. According to Capsule Security findings,

CVE-2026-21520
CSO Online

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21520Vendor Advisory