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Nearly 22,000 Microsoft Exchange servers vulnerable to hijack attacks

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vulnerabilities

Nearly 22,000 Microsoft Exchange servers vulnerable to hijack attacks

Nearly 22,000 Microsoft Exchange servers connected to the internet lack patches for a high-severity authentication bypass vulnerability. This flaw allows attackers to gain unauthorized access to all user mailboxes on affected systems.

Why it matters: Organizations running unpatched Exchange servers face immediate risk of full mailbox compromise and lateral movement into corporate networks, requiring urgent patching to prevent account takeover.

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Correction

Correction recorded as of .

vulnerabilities

Nearly 22,000 Microsoft Exchange servers vulnerable to hijack attacks

Nearly 22,000 Microsoft Exchange servers connected to the internet lack patches for a high-severity authentication bypass vulnerability. This flaw allows attackers to gain unauthorized access to all user mailboxes on affected systems.

Why it matters: Organizations running unpatched Exchange servers face immediate risk of full mailbox compromise and lateral movement into corporate networks, requiring urgent patching to prevent account takeover.

Source published
First seen by Cybersecurity Tracker

Source attribution

Correction

Correction recorded as of .

vulnerabilities

Nearly 22,000 Microsoft Exchange servers vulnerable to hijack attacks

Nearly 22,000 Microsoft Exchange servers connected to the internet lack patches for a high-severity authentication bypass vulnerability. This flaw allows attackers to gain unauthorized access to all user mailboxes on affected systems.

Why it matters: Organizations running unpatched Exchange servers face immediate risk of full mailbox compromise and lateral movement into corporate networks, requiring urgent patching to prevent account takeover.

VendorsMicrosoft
Source published
First seen by Cybersecurity Tracker

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