Privilege escalation via untrusted URL redirection
Published Jun 19, 2026 · Updated Jun 19, 2026
Open redirect in Microsoft 365 Copilot's Business Chat allows remote attackers to elevate privileges through a crafted link. Microsoft identifies the locus as Business Chat URL redirection but has not disclosed the affected endpoint or exact validation failure permitting an untrusted destination. Exploitation requires user interaction; the record reports network reachability, no prior privileges, and potential compromise of confidentiality, integrity, and availability.
Summary
What happened
Open redirect in Microsoft 365 Copilot's Business Chat allows remote attackers to elevate privileges through a crafted link. Microsoft identifies the locus as Business Chat URL redirection but has not disclosed the affected endpoint or exact validation failure permitting an untrusted destination. Exploitation requires user interaction; the record reports network reachability, no prior privileges, and potential compromise of confidentiality, integrity, and availability.
The record
- CVE
- CVE-2026-47645
- Published
- Jun 19, 2026
- Updated
- Jun 19, 2026
- Vendor
- Microsoft
- Product
- Microsoft 365 Copilot
- Classifications
- CWE-601, T1204.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 19, 2026CVE publishedPublication date reported by the CVE source.
- Jun 19, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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