Bleepingcomputer iconBleepingcomputerSep 1, 2026

Nearly 22,000 Microsoft Exchange servers vulnerable to hijack attacks

Nearly 22,000 Microsoft Exchange servers exposed online remain unpatched against a high-severity authentication bypass vulnerability that allows attackers to hijack all user mailboxes.

Nearly 22,000 Microsoft Exchange servers vulnerable to hijack attacks

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Nearly 22,000 Microsoft Exchange servers exposed online remain unpatched against a high-severity authentication bypass vulnerability that allows attackers to hijack all user mailboxes.

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Nearly 22,000 Microsoft Exchange servers exposed online remain unpatched against a high-severity authentication bypass vulnerability that allows attackers to hijack all user mailboxes.

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