# CVE-2026-45659: Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability

- Exploited (CISA KEV): yes, added 2026-07-01, known ransomware use
- Published: 2026-05-22
- CVSS: 8.8 HIGH (v3.1)
- EPSS: 80.2% (100th percentile)
- CWE: CWE-502

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | No public claim | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | No public claim | — | — |
| Fastly | Before feed history | — | — |
| F5 | No public claim | — | — |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

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