CVE-2021-41566
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 · uneditedThe file extension of the TadTools file upload function fails to filter, thus remote attackers can upload any types of files and execute arbitrary code without logging in.
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 confidenceTadTools contains a file upload function that lacks proper file extension filtering, allowing unauthenticated remote attackers to upload arbitrary file types including executable scripts. This enables remote code execution on the affected server.
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< 3.2.2CVSS 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/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 Tadtools installationLocate the Tadtools installation directory and look for files such as class/TadtoolsUpload.php, tadtools.php, or similar core Tadtools filesAffected if Tadtools is present on the system
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Determine installed versionCheck version information in the project's composer.json, package.json, or version file (often in the root directory or in a README file)Affected if Installed version is lower than 3.2.2
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Verify file upload module is presentLook for upload-related PHP files or modules in the Tadtools directory, such as files containing 'upload' in the filenameAffected if The file upload module exists and is accessible via the web server
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Check if upload endpoint is accessible without authenticationAttempt to access the file upload functionality directly via HTTP without providing any login credentialsAffected if The upload endpoint responds without requiring authentication
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Inspect file extension validationExamine the upload handling code (e.g., in TadtoolsUpload.php or similar) to see if there is any file extension filtering in placeAffected if No extension filtering exists, or filtering allows executable extensions such as .php, .phtml, .exe, .sh, or .js
The system is affected if Tadtools versions below 3.2.2 are installed with the file upload module exposed and accessible without authentication, and no extension filtering is implemented.
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 · scoped3.2.2
Implement strict file extension whitelisting, disable script execution in upload directories, and ensure authentication is required for all file upload functionality.
3.2.2
- 1. Back up the current TadTools installation and database before proceeding
- 2. Download TadTools version 3.2.2 from the official source (tadtools website or the project's distribution channel)
- 3. Replace the existing TadTools files with the new version 3.2.2
- 4. Verify that the file upload function now properly filters file extensions and blocks executable file types
- 5. Test that legitimate file uploads still work correctly for allowed file types
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 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 $3,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-41566 — 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-2021-41566 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