CVE-2026-58277: Microsoft SharePoint improper authorization privilege escalation

CVE-2026-58277 · Severity: high · CVSS 8.8 · Published 2026-07-14

Microsoft SharePoint, a widely used platform for document management and team collaboration, contains a security flaw that allows an existing user to gain higher-level administrative permissions. An attacker with basic access to the corporate network could exploit this to access sensitive documents, modify site content, or disrupt business operations. Organizations should apply the latest security updates from Microsoft to prevent unauthorized access to their internal data.

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

Quick answers

Is CVE-2026-58277 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-58277 being exploited in the wild.
How severe is CVE-2026-58277?
High severity, with a CVSS score of 8.8, published 14 July 2026.
Which products and versions are affected?
Microsoft SharePoint Enterprise Server 2016 16.0.0 to 16.0.5561.1001; Microsoft SharePoint Server 2019 16.0.0 to 16.0.10417.20175.
Is there a fix for CVE-2026-58277?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-58277 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-58277?
Check whether you run Microsoft SharePoint Enterprise Server 2016 or Microsoft SharePoint Server 2019 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

An improper authorization vulnerability (CWE-285) exists in Microsoft SharePoint Server 2019 and SharePoint Enterprise Server 2016. The flaw allows a remote attacker with low-privileged user credentials to bypass authorization checks and elevate their privileges within the SharePoint environment. The attack is carried out over the network and does not require user interaction. Successful exploitation grants the attacker high-level access, potentially leading to a full compromise of confidentiality, integrity, and availability of the SharePoint site data. Microsoft has released security updates to address this issue.

Affected products

  • Microsoft SharePoint Enterprise Server 2016 16.0.0 to 16.0.5561.1001
  • Microsoft SharePoint Server 2019 16.0.0 to 16.0.10417.20175

Timeline

  • 2026-07-14: disclosed
  • 2026-07-14: advisory

References

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