RCE in Microsoft SharePoint (widely deployed enterprise software) can allow full server compromise and widespread disruption.
CVE-2026-50522
Remote code execution in Microsoft SharePoint via deserialization of untrusted data.
Is CVE-2026-50522 being exploited?
Yes. CVE-2026-50522 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2026-50522?
CVE-2026-50522 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-50522?
Yes. A fix has been recorded for CVE-2026-50522. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-50522 affect?
CVE-2026-50522 affects Microsoft SharePoint, SharePoint Server, Microsoft Office SharePoint Server. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-50522?
Apply vendor patch immediately; isolate SharePoint servers and block external access until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote code execution over network; attacker can run arbitrary code and gain full control of SharePoint servers.
Immediate action required
- affected>= 16.0.0 and < 16.0.5561.1001
- affected>= 16.0.0 and < 16.0.10417.20175
- affected>= 16.0.0 and < 16.0.19725.20434
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.