CVE-2026-55019 Microsoft CVE debrief

Who should care

Defenders responsible for Microsoft SharePoint Server deployments should assess exposure and prioritize patching. This includes administrators, security teams, and IT personnel who manage SharePoint Server environments. They should verify affected SharePoint Server versions and apply vendor patches to prevent exploitation. Additionally, defenders should monitor for suspicious activity and assess the exposure of Share

Why it matters

Defenders should prioritize verifying affected SharePoint Server versions and applying vendor patches to prevent exploitation.

• Verify and apply patches to prevent exploitation
• Monitor for suspicious activity
• Assess exposure of SharePoint Server deployments

Technical summary

The vulnerability exists in Microsoft SharePoint Server due to improper neutralization of input during web page generation. This allows an authorized attacker to perform spoofing over a network. The vulnerability can be exploited by an attacker with authorized access to the SharePoint Server. Defenders should prioritize verifying affected SharePoint Server versions and applying vendor patches to prevent exploitation.

Defensive priority

Defenders should prioritize verifying affected SharePoint Server versions and applying vendor patches.

Recommended defensive actions

• Verify affected SharePoint Server versions
• Apply vendor patches
• Monitor for suspicious activity

Evidence notes

The CVE Program and NVD provide official records of the vulnerability. Microsoft has released a patch for the vulnerability. The vulnerability was publicly disclosed on 2026-07-14T17:08:33.303Z. The CVE record has not been modified since then. The vulnerability affects Microsoft SharePoint Server. The CVE Program and NVD provide official records of the vulnerability, which helps defenders verify the existence of the vulnerability and apply patches accordingly.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.