Microsoft 365 Copilot Chat vulnerabilities

• microsoft 365 copilot's business chat, 365 copilot chat +1 more Microsoft 365 Copilot Business Chat Information Disclosure Vulnerability CVE-2026-78501 8.6 HighSeptember 17, 2026
• microsoft 365 copilot chat, 365 copilot's business chat +1 more M365 Copilot Information Disclosure Vulnerability CVE-2026-26129 7.5 HighMay 7, 2026
• microsoft 365 copilot chat, 365 copilot's business chat +1 more M365 Copilot Information Disclosure Vulnerability CVE-2026-26164 7.5 HighMay 7, 2026
• microsoft exchange online, microsoft 365 copilot chat, exchange online +2 more Microsoft Exchange Elevation of Privilege Vulnerability CVE-2026-26137 9.9 CriticalMarch 19, 2026
• microsoft 365 copilot chat, 365 copilot's business chat +1 more Copilot Information Disclosure Vulnerability CVE-2025-59286 9.3 CriticalOctober 9, 2025
• microsoft 365 copilot chat, 365 copilot's business chat +1 more Copilot Information Disclosure Vulnerability CVE-2025-59272 9.3 CriticalOctober 9, 2025
• microsoft 365 copilot chat, 365 copilot's business chat +1 more Microsoft 365 Copilot BizChat Information Disclosure Vulnerability CVE-2025-53787 8.2 HighAugust 7, 2025
• microsoft 365 copilot chat, 365 copilot's business chat +1 more Microsoft 365 Copilot BizChat Information Disclosure Vulnerability CVE-2025-53774 6.5 MediumAugust 7, 2025