Summary of Impact
On November 19, 2025, between approximately 9:00 AM and 10:36 AM UTC, some ShareFile customers experienced issues logging in to the service. The incident resulted in a partial login outage, primarily affecting users in the EU region, with intermittent impact in other regions.
Root Cause
The incident was triggered by an unusually high volume of SMS-based MFA requests that overwhelmed the ShareFile login service. This surge in MFA traffic caused resource exhaustion in backend systems responsible for authentication, leading to login failures. Temporary configuration limits and capacity constraints contributed to the inability to process requests efficiently during the peak.
Mitigation
The operations and engineering teams responded by:
Enforcing further restrictions and rate limits for SMS-based MFA to prevent excessive requests.
Modifying backend system configurations to handle higher login volumes.
Once these actions were completed, normal login functionality was restored.
Next Steps
To prevent recurrence, ShareFile will:
Continue to refine and enforce limits on SMS-based MFA requests.
Strengthen monitoring and detection of excessive MFA activity targeting authentication systems.
We apologize for any inconvenience this incident may have caused. For ongoing updates and incident history, please visit the ShareFile Status Page.