CVE-2026-64901
HIGH 8.8Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
ELEVATED IMPACT
Severe if exploited (CVSS 8.8), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
1.9%chance of exploitation in 30 days · 78th percentile
○ In CISA KEV
○ Public exploit / PoC
Impact if exploited
8.8CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-64901/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-64901/poc.json
Affected
Vendors Microsoft
Products Microsoft Sharepoint Enterprise Server 2016 Microsoft Sharepoint Server 2019 Microsoft Sharepoint Server Subscription Edition Sharepoint Server
Weakness (CWE)
- CWE-502: : Deserialization of Untrusted Data
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Microsoft | Sharepoint Server | < 16.0.19725.20522 |
| Microsoft | Sharepoint Server | 2016 |
| Microsoft | Sharepoint Server | 2019 |
All CVSS metrics
- HIGH 8.8 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - HIGH 8.8 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H