CVE-2026-45479
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 · uneditedImproper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.
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 cross-site scripting (XSS) vulnerability in Microsoft Office SharePoint where improper input neutralization allows an authenticated attacker to inject malicious scripts into web pages, potentially leading to session hijacking and spoofing of other authorized users.
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< 16.0.19725.20384= 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
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
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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Check SharePoint Server versionOpen SharePoint Management Shell and run: (Get-SPFarm).BuildVersion or check via Central Administration > System Settings > Manage servers in this farmAffected if The version returned is 2016, 2019, or lower than 16.0.19725.20384
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Confirm SharePoint edition and buildRun Get-SPFarm | Select-Object -Property Name, BuildVersion, Version to display the full version string and confirm it matches the affected rangesAffected if BuildVersion is less than 16.0.19725.20384, or version displays as 2016 or 2019 (any build)
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Identify customizations or web parts accepting user inputReview installed web parts and custom solutions via Central Administration > Web Designer Galleries > Web Parts, or run Get-SPWebPartPackage in PowerShellAffected if Custom or third-party web parts that accept user input are deployed and not internally validated
Your environment is affected if the installed SharePoint Server version is 2016, 2019, or any version earlier than 16.0.19725.20384.
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 · scoped16.0.19725.20384
Apply Microsoft security patches for SharePoint when available; implement input validation, output encoding, and Content Security Policy headers as compensating controls until patch deployment.
SharePoint Server 2016/2019 to version 16.0.19725.20384 or later
- Check the current SharePoint Server version by going to Central Administration > System Settings > Manage servers in this farm
- Navigate to Microsoft Update Catalog or the Microsoft Security Response Center (msrc.microsoft.com) to obtain the security update for this vulnerability
- Apply the appropriate security update for your SharePoint version (2016 or 2019) that includes the fix for CVE-2026-45479
- After installation, verify the version matches or exceeds 16.0.19725.20384 using the SharePoint Management Shell command: (Get-SPFarm).BuildVersion
- Test critical SharePoint workflows to ensure normal functionality post-update
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45479 — 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-2026-45479 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