CVE-2026-20963 | BDVDB-2026-310482 Detail

MicrosoftMicrosoft SharePoint Enterprise Server 2016

Description#

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

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.

Weaknesses#

CWE-502 Deserialization of Untrusted Data

References#

Exploit#

No public exploit known

History#

Version 12026-01-13Record published in the CVE List.
Version 22026-07-30Most recent update recorded in the CVE List.

Published

Published: 2026-01-13
Last modified: 2026-07-30

Vendor information

Vendor: Microsoft
Product: Microsoft SharePoint Enterprise Server 2016

All Microsoft vulnerabilities

Score

9.8 Critical

EPSS

29.2%, Moderate

Estimated chance of exploitation in the next 30 days. EPSS percentile: 98.2.

KEV

Yes

Listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Insecure Deserialization

Action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Affected Systems

Vulnerable
>= 16.0.0 and < 16.0.5535.1001
Fixed
16.0.5535.1001

Scoring System

CVSS v4.0

Not available

CVSS v3.1

9.8 Critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None
User Interaction	None
Scope	Unchanged
Confidentiality	High
Integrity	High
Availability	High

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).