CVE-2026-50522 | Microsoft SharePoint Remote Code Execution Vulnerability

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

Published: 2026-07-14 Last update: 2026-07-15 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-50522 is rated High Risk (73.8/100): CVSS Critical severity, with high exploitation likelihood (EPSS 20.35%, 97th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-50522

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-07-16 19.72% 20.35% +0.63%
2 2026-07-15 19.72%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-50522

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]

Weakness enumeration for CVE-2026-50522

GitHub Security Advisory for CVE-2026-50522

GHSA-ww8x-9jc5-9v7f · Severity: critical — Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker...

Affected software / configurations for CVE-2026-50522

Vendor Product Version Raw CPE
microsoft sharepoint_server < 16.0.19725.20434 cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*
microsoft sharepoint_server 2016 cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
microsoft sharepoint_server 2019 cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*

References for CVE-2026-50522

cvelogic Threat Intelligence