CVE-2026-55052
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedMissing authorization in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.
In the news
Third-party coverage- Microsoft July 2026 Patch Tuesday fixes massive 570 flaws, 3 zero-days
- Microsoft CVE Summary - Bleeping Computer
Surfaced from public web coverage — external links open in a new tab.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceThis is a broken access control vulnerability in Microsoft Office SharePoint where the application fails to properly validate authorization for certain operations. An authenticated attacker with existing low-privilege access can exploit the missing authorization checks to perform actions reserved for higher-privileged users, effectively escalating their privileges within the SharePoint environment.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 16.0.19725.20434= 2016= 2019CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify SharePoint Server versionRun Get-SPFarm | Select-Object BuildVersion in SharePoint Management Shell, or check Central Administration > System Settings > Manage farm configuration. You can also check the file version of STS.exe in C:\Program Files\Common Files\microsoft shared\Web Server Extensions\16\BINAffected if The version is less than 16.0.19725.20434, or equals 2016 or 2019 exactly
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Confirm SharePoint edition and buildIn SharePoint Management Shell, run (Get-SPFarm).BuildVersion to get the full version number. Cross-reference with Microsoft documentation to determine if your specific build falls within the vulnerable rangeAffected if Build version is below 16.0.19725.20434 for Subscription/Current channel, or the product is SharePoint Server 2016 or 2019 (any build)
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Review user permission levelsIn SharePoint Central Administration > Application Management > Manage web application > User Policy, enumerate all users and their permission levels. Check for users granted Full Control or Farm Administrator roles who should not have those privilegesAffected if Low-privilege users exist alongside high-privilege users without proper role separation
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Audit SharePoint groups and role assignmentsUse SharePoint Management Shell: Get-SPSite -Limit All | Get-SPWeb -Limit All | Get-SPUser -Web $_.Url to list all users and their assigned roles. Compare assigned roles against expected baseline permissionsAffected if Users with lower-tier permissions (such as Contributor or Viewer) are found in groups or have role assignments typically reserved for higher-privilege roles like Full Control or Administrator
You are affected if your SharePoint Server version is 2016, 2019, or any build below 16.0.19725.20434 and you have multiple user permission levels configured.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped16.0.19725.20434
Apply Microsoft security patches for SharePoint when available. If no patch exists, implement proper authorization checks at all privilege-sensitive operations and conduct access control audits. Restrict user permissions to the minimum required until the vulnerability is remediated.
SharePoint Server 2016 or 2019 with version 16.0.19725.20434 or later (apply latest Cumulative Update)
- Verify current SharePoint Server version by navigating to Central Administration > System Settings > Manage servers in this farm
- Download the latest SharePoint Server update from Microsoft Update Catalog or Microsoft Download Center
- Review Microsofts update installation documentation for your specific SharePoint version (2016 or 2019)
- Back up all SharePoint databases and farm configurations before applying updates
- Run the update installer on all servers in the SharePoint farm following a staged rollout approach
- After installation, run the SharePoint Products Configuration Wizard on each server
- Verify successful update by checking the version in Central Administration matches or exceeds 16.0.19725.20434
- Test critical SharePoint workflows and permissions to confirm the authorization fix is functioning
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,888.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-55052 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-55052 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data