CVE-2023-0670
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 · uneditedUlearn version a5a7ca20de859051ea0470542844980a66dfc05d allows an attacker with administrator permissions to obtain remote code execution on the server through the image upload functionality. This occurs because the application does not validate that the uploaded image is actually an image.
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 · high confidenceUlearn allows administrators to upload images through a file upload feature that lacks proper file validation. The application does not verify that uploaded files are actually images (missing content-type, magic byte, or image processing validation), enabling an attacker to upload malicious executable files that can be triggered for remote code execution.
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 dataall versionsCVSS 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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/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 the file upload endpoint in UlearnLocate the web routes or API endpoints that handle image uploads by reviewing the application's routing configuration, JavaScript files, or HTML forms. Common paths include /upload, /api/upload, or similar. Test accessing these endpoints to confirm the upload feature exists.Affected if The file upload endpoint exists and is accessible in the application.
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Verify if uploaded files undergo content-type validationReview the server-side code or configuration handling the upload endpoint. Search for logic that checks the Content-Type, MIME type, or similar headers on uploaded files. Look for whitelisting or validation of file types.Affected if No content-type or MIME type validation is performed on uploaded files.
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Verify if uploaded files undergo magic byte validationReview the server-side code to check if uploaded files are validated by examining their file signatures (magic bytes). Look for code that reads the first few bytes of uploaded files and compares them against known image headers.Affected if No magic byte or file signature validation is performed on uploaded files.
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Verify if uploaded files undergo image processing validationReview the server-side code to check if uploaded files are processed through an image processing library (such as Pillow, ImageMagick, or similar) that attempts to render, parse, or validate the image.Affected if Uploaded files are not processed through an image parsing or rendering library.
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Check file storage configurationReview the application configuration or code that handles file storage. Determine where uploaded files are stored and whether they are placed outside the web root with randomly generated filenames.Affected if Uploaded files are stored within the web root or with predictable/sequential filenames, allowing direct access via URL.
The environment is affected if the file upload feature is accessible and any of the following is true: no content-type validation, no magic byte validation, no image processing validation is performed, or files are stored within the web root with predictable names.
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.
From vendor dataImplement strict file validation: verify file magic bytes, use an image processing library to attempt rendering/parsing the uploaded file, enforce allowlists for permitted image formats, and store uploads outside the web root with random filenames.
- Consultation2.0 h
- Implementation8.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-0670 — 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-2023-0670 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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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.
- 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