Microsoft Defender Misclassifies Legitimate Google Search Links as Threats
Microsoft is investigating a false positive issue in Defender for Office 365 where legitimate Google search result links are incorrectly flagged as unsafe. Users attempting to open these links receive a warning stating the website may be insecure, and the problem persists even when copying and pasting URLs directly into browsers. The incident, tracked under advisory MO1465962, stems from erroneous classification by the Safe Links feature, which rewrites and rechecks URLs in email, Teams, and Microsoft 365 applications. The misclassification affects not only end users but also generates alerts for administrators in the Microsoft Defender Portal and Microsoft Sentinel SIEM platform. Safe Links is designed to protect against phishing by validating links at click time, but in this case it overreacted by blocking entire Google search URLs. Microsoft has not disclosed the number of impacted customers or affected regions and continues working on a fix for the erroneous classification.
AntiMalwareSep 2, 2026Translated from Russian