CVE-2026-50522
Analyzed
Published: 14 Jul 2026, 17:05
Last modified:20 Aug 2026, 17:01
Vulnerability Summary
Overall Risk (default)
high
70/100 CVSS Score
9.8 CRITICAL
v3.1 (cve.org)
EPSS Score
76.98% CRITICAL
77% probability 0.00%
KEV
Listed
CISA
1 listing
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected
Timeline
14 Jul 2026, 17:05
Published
Vulnerability first disclosed
22 Jul 2026, 00:00
Added to CISA KEV
Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
25 Jul 2026, 00:00
CISA Remediation Due
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
20 Aug 2026, 17:01
Last Modified
Vulnerability information updated
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
CVSS Metrics
- v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
- v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Trends
Current EPSS score: 76.98%• Percentile: 100%
Techniques & Countermeasures
- CWE-502•Deserialization of Untrusted Data
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Affected Systems
- microsoft•microsoft sharepoint enterprise server 2016
≥ 16.0.0, < 16.0.5561.1001
- microsoft•microsoft sharepoint server 2019
≥ 16.0.0, < 16.0.10417.20175
- microsoft•microsoft sharepoint server subscription edition
≥ 16.0.0, < 16.0.19725.20434
- microsoft•sharepoint_server
< 16.0.19725.20434 | 2016 | 2019