CVE-2026-50522: Microsoft SharePoint remote code execution via unsafe deserialization

CVE-2026-50522 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2026-07-14

Microsoft SharePoint, a widely used collaboration and document management platform, contains a critical security flaw that allows remote attackers to take control of the server. An unauthorized user can exploit this vulnerability over the network to execute malicious commands, potentially leading to full data theft or service disruption. This vulnerability has been reported as exploited in the wild, making immediate patching essential to protect corporate data and operations.

Technologies: Microsoft SharePoint, Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition. Vendors: Microsoft.

Quick answers

Is CVE-2026-50522 exploited in the wild?
Yes. CVE-2026-50522 is known to be exploited in the wild, first recorded on 22 July 2026. Treat it as urgent.
How severe is CVE-2026-50522?
Critical severity, with a CVSS score of 9.8, published 14 July 2026.
Which products and versions are affected?
Microsoft SharePoint Enterprise Server 2016 16.0.0 to < 16.0.5561.1001, Prior to 16.0.5561.1001; Microsoft SharePoint Server 2019 16.0.0 to < 16.0.10417.20175, Prior to 16.0.10417.20175; Microsoft SharePoint Server Subscription Edition 16.0.0 to < 16.0.19725.20434, Prior to 16.0.19725.20434.
Is there a fix for CVE-2026-50522?
A patch was published on 2026-07-15: Patch information added to NVD record Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-50522 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-50522?
Check whether you run Microsoft SharePoint, Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019 or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A critical deserialization vulnerability (CWE-502) exists in Microsoft SharePoint Server. The flaw stems from the improper handling of untrusted data during deserialization, which allows an unauthenticated attacker to achieve remote code execution (RCE). The attack can be carried out over the network without any user interaction or prior privileges. Affected versions include SharePoint Server 2016, 2019, and Subscription Edition. Microsoft has released security updates to address this issue, and CISA has confirmed active exploitation in the wild.

Affected products

  • Microsoft SharePoint Server 2019 Prior to 16.0.10417.20175
  • Microsoft SharePoint Enterprise Server 2016 Prior to 16.0.5561.1001
  • Microsoft SharePoint Server Subscription Edition Prior to 16.0.19725.20434

Timeline

  • 2026-07-14: disclosed: Initial disclosure by Microsoft Corporation
  • 2026-07-15: patched: Patch information added to NVD record
  • 2026-07-22: kev added: Added to CISA Known Exploited Vulnerabilities catalog

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