CVE-2026-33110 | Microsoft SharePoint Server Remote Code Execution Vulnerability

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

Published: 2026-05-12 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-33110 is rated Moderate Risk (61.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.83%). Mandatory action: Review affected assets and schedule 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-2026-33110

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 2026-05-30 0.56% 0.83% +0.27%
2 2026-05-14 0.50% 0.56% +0.05%
3 2026-05-13 0.50%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33110

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/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:L)
A normal user session is enough; they don’t have to be admin.
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.
2.8 5.9 [email protected]

Weakness enumeration for CVE-2026-33110

GitHub Security Advisory for CVE-2026-33110

GHSA-pqmq-26jw-5r2g · Severity: high — Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to...

Affected software / configurations for CVE-2026-33110

Vendor Product Version Raw CPE
microsoft sharepoint_server < 16.0.19725.20280 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-2026-33110

cvelogic Threat Intelligence