Microsoft Teams
Security incidents tagged Microsoft Teams. Newest first.
1 Microsoft Teams incident in the last 12 months
- Incidents
- 1
- Live
- 1
- Patched
- 0
- Days without an incident
- 0
- Longest quiet run: 8 days (Oct 20–Oct 27)
- MediumPartly patched
Fake IT help desk calls breach at least four Bay Street law firms' Microsoft 365 data
A voice phishing campaign is breaching Canadian law firms. Callers pose as internal IT support by phone or Microsoft Teams, claim an urgent passkey, MFA or password change, and send staff to firm-branded fake sign-in pages that relay credentials and MFA to the real identity provider in real time. The attackers then register their own MFA devices, delete security notifications, pull data from Microsoft 365 (SharePoint, OneDrive) with scripts and Microsoft Graph, and send extortion demands, according to the Canadian Centre for Cyber Security's Oct 28 2026 alert. The Globe and Mail reports at least four Bay Street firms were compromised: McCarthy Tétrault, Davies Ward Phillips & Vineberg, Borden Ladner Gervais (part of its Microsoft cloud environment, including client files) and Bennett Jones (two business services staff accounts on Oct 19; client revenue reports and some mandate descriptions taken, document management and accounting systems not breached).
Canadian law firms' Microsoft 365 environments (help desk vishing campaign)Since Oct 19, 2026
