Unrestricted File UploadWeakness · CWE-434

CVE-2026-39527

MEDIUM · 5.4 CVSS v3.1 Published 2026-06-15
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
60/100
Remediation priority · Elevated
Remotely reachable Zero-click

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 · unedited
Subscriber Arbitrary File Upload in WpStream < 4.11.2 versions.

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 confidence

The WpStream WordPress plugin before version 4.11.2 allows subscriber-level users to upload arbitrary files to the server. This improper authorization vulnerability enables authenticated users with minimal privileges to potentially upload malicious PHP scripts or other executable files, possibly leading to remote code execution.

MitigationUpdate WpStream plugin to version 4.11.2 or later. Until then, consider restricting or disabling subscriber-level user registration and monitor for suspicious file uploads.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS 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
None
Integrity
Low
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

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 checks

Work through these to decide whether this CVE applies to you.

  1. Verify WpStream plugin is installed
    Check the WordPress plugins directory or use wp-cli: wp plugin list --status=active --field=name | grep -i wpstream
    Affected if WpStream plugin is present and active in the WordPress installation
  2. Check WpStream plugin version
    View the plugin header file (usually main plugin file) in the wpstream plugin directory or use wp-cli: wp plugin get wpstream --field=version
    Affected if Installed version is earlier than 4.11.2 (for example, 4.11.1 or below)
  3. Confirm subscriber role is enabled
    Check WordPress user roles via wp-admin under Users > Roles, or use wp-cli: wp role list --fields=name. Also verify if user registration is allowed in Settings > General > Membership
    Affected if Subscriber role exists and new user registration is enabled in the WordPress settings
  4. Inspect upload directories for suspicious files
    Review the wp-content/uploads/ directory (and any custom upload paths) for unexpected PHP files, scripts, or executable files that were recently uploaded
    Affected if Unknown PHP files or executable content is present in upload directories and the above version condition is true

You are affected if the WpStream plugin version is below 4.11.2 AND the subscriber role is accessible for user registration, allowing authenticated users with minimal privileges to potentially upload arbitrary files.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update WpStream plugin to version 4.11.2 or later. Until then, consider restricting or disabling subscriber-level user registration and monitor for suspicious file uploads.

Recommended fix High confidence

WpStream 4.11.2

  1. 1. Backup your WordPress site before making any changes
  2. 2. Update the WpStream plugin to version 4.11.2 or later through the WordPress admin dashboard (go to Plugins > Installed Plugins > WpStream > Update Now)
  3. 3. Alternatively, upload the latest version from wordpress.org via Plugins > Add New > Upload Plugin
  4. 4. Verify the update was successful by checking the plugin version
  5. 5. Test that the streaming functionality works correctly after the update
  6. 6. Consider reviewing user role permissions to ensure only trusted roles have upload capabilities

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-39527 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-39527 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • 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