Exploited CVEs / Microsoft / CVE-2026-58644
CVE-2026-58644
Updated July 22, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Actively exploited Microsoft SharePoint vulnerability. Added to the CISA KEV catalog 2026-07-16.
All about CVE-2026-58644: the Senserva AI read, the CISA required action and deadline, the official fix, what the press says about it, and the questions admins ask.
Microsoft SharePoint Deserialization of Untrusted Data Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2026-07-19 (that deadline has passed); treat that date as the outer bound for your own environment. The fix is in the vendor advisory: Microsoft Security Update Guide (MSRC), linked below.
Risk summary
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Senserva AI Opinion for CVE-2026-58644
CVE-2026-58644 is a critical (CVSS 9.8) unauthenticated remote code execution flaw in on-premises SharePoint, hitting Enterprise Server 2016, Server 2019, and the Subscription Edition. CISA added it to the KEV catalog on 2026-07-16, so exploitation is confirmed in the wild against internet-facing SharePoint farms, which are a common initial access point into corporate networks.
Do this: Apply Microsoft's SharePoint patch to all affected 2016, 2019, and Subscription Edition servers now, and hunt for signs of web shell drops or unexpected process execution on any farm that was exposed before patching.
AI-generated from public data, 2026-07-22. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-58644
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-58644
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
What the press says about CVE-2026-58644
Trusted-source coverage, pulled live from their own feeds.
CISA required action
Federal (BOD 22-01) remediation due date: 2026-07-19 (past due).
Official fix for CVE-2026-58644
The authoritative fix and affected-version list are published by the vendor. Find the SharePoint advisory on Microsoft Security Update Guide (MSRC).
Common questions about CVE-2026-58644
Is CVE-2026-58644 actively exploited?
Yes. CVE-2026-58644 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2026-07-16, which means exploitation in the wild has been confirmed, not predicted.
What is the CISA deadline and required action for CVE-2026-58644?
CISA set the federal (BOD 22-01) remediation due date at 2026-07-19, which has passed; treat any unremediated system as overdue.
What fixes CVE-2026-58644?
The authoritative fix is in the vendor advisory: see Microsoft Security Update Guide (MSRC) for the patched SharePoint versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.
Can I ask my own AI about CVE-2026-58644?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-58644's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed three times a day (5 AM, 12:30 PM, and 7 PM US Central).
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Authoritative references
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