Microsoft Patch Tuesday for January 2023 — Snort rules and prominent vulnerabilities

Summary: Microsoft's January 2023 security update disclosed 98 vulnerabilities: 11 rated Critical, 87 rated Important, and none Moderate. Microsoft rates all Critical flaws as less likely or unlikely to be exploited except CVE-2023-21743, a low-complexity SharePoint Server security bypass an unauthenticated attacker can trigger with an anonymous connection.
Key Takeaway: CVE-2023-21743 is the one Critical flaw Microsoft does not discount, and it needs no credentials - an anonymous connection to a SharePoint server is enough, so any internet-facing SharePoint instance is the exposure to check first.

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Topics: Vulnerabilities & Patching
Mentions: CVE-2023-21535 CVE-2023-21543 CVE-2023-21546 CVE-2023-21548 CVE-2023-21555 CVE-2023-21556 CVE-2023-21679 CVE-2023-21730 CVE-2023-21743 CVE-2023-21779
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