Known Exploited Vulnerability
9.8
CRITICAL CVSS 3.1
CVE-2026-56164
Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability - [Actively Exploited]
Description

Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.

INFO

Published Date :

July 14, 2026, 5:17 p.m.

Last Modified :

July 14, 2026, 9:10 p.m.

Remotely Exploit :

Yes !
CISA Notification
CISA KEV (Known Exploited Vulnerabilities)

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.

Description :

Microsoft SharePoint contains a missing authentication for critical function vulnerability that allows an unauthorized attacker to elevate privileges over a network.

Required Action :

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.

Known Ransomware Campaign Use:

Unknown

Notes :

https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-56164 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-56164

Affected Products

The following products are affected by CVE-2026-56164 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Microsoft sharepoint_server
2 Microsoft sharepoint_enterprise_server_2016
3 Microsoft sharepoint_server_2016
4 Microsoft sharepoint_server_2019
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM f38d906d-7342-40ea-92c1-6c4a2c6478c8
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 CRITICAL [email protected]
Public PoC/Exploit Available at Github

CVE-2026-56164 has a 7 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-56164.

URL Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164 Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164 US Government Resource
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-56164 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

End-to-end technical analysis and reproduction notes for high-impact CVEs (e.g., pre-auth RCEs, sandbox escapes, and privilege escalations).

Updated: 1 week, 5 days ago
0 stars 0 fork 0 watcher
Born at : July 21, 2026, 3:46 a.m. This repo has been linked 13 different CVEs too.

CVE-2026-56164 EOP Exploit

Updated: 2 weeks, 1 day ago
15 stars 0 fork 0 watcher
Born at : July 15, 2026, 8:53 a.m. This repo has been linked 1 different CVEs too.

An operational threat hunting and detection suite. Maps network and host log queries directly to the MITRE ATT&CK framework, featuring an evidence-driven attribution engine that dynamically correlates indicators to state-sponsored threat actors.

HTML CSS JavaScript

Updated: 2 weeks, 5 days ago
0 stars 0 fork 0 watcher
Born at : May 1, 2026, 12:35 p.m. This repo has been linked 5 different CVEs too.

Panel de ciberamenazas que se actualiza solo: nuevas amenazas y vulnerabilidades activas cada 6 horas.

CSS Python HTML JavaScript

Updated: 2 weeks, 1 day ago
0 stars 0 fork 0 watcher
Born at : Jan. 28, 2026, 12:11 a.m. This repo has been linked 16 different CVEs too.

None

Ruby Shell Python

Updated: 2 weeks, 4 days ago
1 stars 0 fork 0 watcher
Born at : Nov. 6, 2025, 3:20 a.m. This repo has been linked 4 different CVEs too.

None

Python

Updated: 2 weeks, 1 day ago
2 stars 1 fork 1 watcher
Born at : Oct. 29, 2024, 8:10 p.m. This repo has been linked 10 different CVEs too.

None

Python

Updated: 2 weeks, 2 days ago
0 stars 0 fork 0 watcher
Born at : Sept. 13, 2024, 9:56 p.m. This repo has been linked 4 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-56164 vulnerability anywhere in the article.

  • security.nl
Honderden Microsoft SharePoint-servers bevatten actief misbruikte lekken

Honderden Microsoft SharePoint-servers die vanaf het internet toegankelijk zijn bevatten bekende kwetsbaarheden waar aanvallers op dit moment actief misbruik van maken. Het gaat ook om 25 SharePoint-s ... Read more

Published Date: Jul 27, 2026 (1 week ago)
  • The Hacker News
Critical SharePoint RCE CVE-2026-50522 Under Active Exploitation After Public PoC

A third SharePoint Server flaw patched by Microsoft as part of its Patch Tuesday update for July 2026 has come under active exploitation, per watchTowr. The vulnerability in question is CVE-2026-50522 ... Read more

Published Date: Jul 21, 2026 (1 week, 6 days ago)
  • The Cyber Express
The Cyber Express Weekly Roundup: TikTok Age Verification Probe, Healthcare Data Breach, Qantas Ruling, and Major Cyberattacks

This week’s cybersecurity roundup highlights growing concerns around online child safety, healthcare data protection, supply chain risks, and cyber threats affecting organizations worldwide. From regu ... Read more

Published Date: Jul 17, 2026 (2 weeks, 3 days ago)
  • security.nl
Microsoft meldt alsnog actief misbruik van kritiek SharePoint-lek

Een kritieke kwetsbaarheid in Microsoft SharePoint waardoor aanvallers SharePoint-servers op afstand kunnen overnemen is toch wel actief bij aanvallen misbruikt voordat een beveiligingsupdate beschikb ... Read more

Published Date: Jul 17, 2026 (2 weeks, 3 days ago)
  • The Hacker News
CISA Adds Exploited SharePoint RCE Zero-Day CVE-2026-58644 to KEV

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Thursday added a newly patched security flaw impacting Microsoft SharePoint Server to its Known Exploited Vulnerabilities (KEV) cata ... Read more

Published Date: Jul 17, 2026 (2 weeks, 3 days ago)
  • Kaspersky
Key vulnerabilities of Microsoft’s July 2026 Patch Tuesday

Although experts had already warned of an impending “tsunami of vulnerabilities” back in April, immediately following the announcement of the Mythos AI model, concrete evidence began to emerge over th ... Read more

Published Date: Jul 15, 2026 (2 weeks, 5 days ago)
  • The Hacker News
Researcher Drops New Windows Zero-Day PoC Hours After Microsoft Patch Tuesday

Security researcher Chaotic Eclipse (aka Nightmare-Eclipse) has released a new proof-of-concept (PoC) exploit called LegacyHive. It has been described as a Windows User Profile Service arbitrary hive ... Read more

Published Date: Jul 15, 2026 (2 weeks, 5 days ago)
  • The Cyber Express
Microsoft’s Largest Patch Tuesday Fixes 622 Vulnerabilities, Two Under Active Attack

Microsoft Patch Tuesday July 2026 delivered the company’s largest security update to date, addressing 622 Microsoft CVEs, more than tripling the roughly 200 vulnerabilities patched in June. Among the ... Read more

Published Date: Jul 15, 2026 (2 weeks, 5 days ago)
  • security.nl
Microsoft komt met grootste Patch Tuesday ooit: 622 kwetsbaarheden gefixt

Microsoft heeft gisteren tijdens Patch Tuesday het grootste aantal kwetsbaarheden ooit verholpen, namelijk 622. Het techbedrijf liet een aantal dagen geleden weten dat klanten en gebruikers als gevolg ... Read more

Published Date: Jul 15, 2026 (2 weeks, 5 days ago)
  • security.nl
Microsoft SharePoint-servers aangevallen, VS roept op tot extra beveiliging

Aanvallers maken actief misbruik van verschillende kwetsbaarheden voor het aanvallen van Microsoft SharePoint-servers, zo waarschuwt het Amerikaanse cyberagentschap CISA. Dat roept organisaties op om ... Read more

Published Date: Jul 15, 2026 (2 weeks, 5 days ago)
  • CrowdStrike.com
July 2026 Patch Tuesday: Microsoft Patches 622 Vulnerabilities Including Two Exploited Zero-Days

Microsoft has addressed 622 vulnerabilities in its July 2026 security update release. Based on CrowdStrike’s analysis, this represents roughly triple the number of vulnerabilities in June, and almost ... Read more

Published Date: Jul 15, 2026 (2 weeks, 5 days ago)
  • The Hacker News
Microsoft Patches Record 622 Flaws, Including Two Zero-Days Under Active Attack

Microsoft shipped its largest Patch Tuesday on record today, and two of the fixes close holes that attackers are already exploiting. The release covers 622 of Microsoft's own CVEs by its Security Upda ... Read more

Published Date: Jul 14, 2026 (2 weeks, 6 days ago)

The following table lists the changes that have been made to the CVE-2026-56164 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Jul. 14, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CPE Configuration OR *cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:* *cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:* *cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:* versions up to (excluding) 16.0.19725.20434
    Added Reference Type Microsoft Corporation: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164 Types: Vendor Advisory
    Added Reference Type CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164 Types: US Government Resource
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 14, 2026

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164
    Added SSVC {'id': 'CVE-2026-56164', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-14T18:45:11.388695Z'}
  • CVE CISA KEV Update by 9119a7d8-5eab-497f-8521-727c672e3725

    Jul. 14, 2026

    Action Type Old Value New Value
    Added Date Added 2026-07-14
    Added Due Date 2026-07-14
    Added Required Action 2026-07-14
    Added Vulnerability Name 2026-07-14
  • New CVE Received by [email protected]

    Jul. 14, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Microsoft', 'product': 'Microsoft SharePoint Enterprise Server 2016', 'versions': [{'status': 'affected', 'version': '16.0.0', 'lessThan': '16.0.5561.1001', 'versionType': 'custom'}], 'platforms': ['x64-based Systems']}, {'vendor': 'Microsoft', 'product': 'Microsoft SharePoint Server 2019', 'versions': [{'status': 'affected', 'version': '16.0.0', 'lessThan': '16.0.10417.20175', 'versionType': 'custom'}], 'platforms': ['x64-based Systems']}, {'vendor': 'Microsoft', 'product': 'Microsoft SharePoint Server Subscription Edition', 'versions': [{'status': 'affected', 'version': '16.0.0', 'lessThan': '16.0.19725.20434', 'versionType': 'custom'}], 'platforms': ['x64-based Systems']}]
    Added Description Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
    Added CWE CWE-306
    Added Reference https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.