WordPressCMS
CVE-2018-1000773
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 · uneditedWordPress version 4.9.8 and earlier contains a CWE-20 Input Validation vulnerability in thumbnail processing that can result in remote code execution due to an incomplete fix for CVE-2017-1000600. This attack appears to be exploitable via thumbnail upload by an authenticated user and may require additional plugins in order to be exploited however this has not been confirmed at this time.
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 confidenceWordPress versions 4.9.8 and earlier contain an incomplete fix for CVE-2017-1000600 in thumbnail processing. The CWE-20 Input Validation vulnerability allows authenticated users to upload thumbnails that can result in remote code execution, likely through insufficient validation of uploaded image files.
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
WordPressCMS
<= 4.9.8CVSS 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:3.0/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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Verify WordPress versionCheck the wp-includes/version.php file for the $wp_version variable, or view the meta generator tag in the page source of any WordPress admin page, or check the Dashboard > At a Glance pageAffected if The installed version is 4.9.8 or any earlier version (versions 4.9.8 and earlier are affected)
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Confirm user upload capability existsExamine WordPress user roles and capabilities, specifically looking for the 'upload_files' capability assigned to user roles. Check if non-administrator accounts (such as Authors, Editors, or Contributors) retain the ability to upload media files in Settings > Media or via user role capabilitiesAffected if Authenticated users with lower privileges (Authors, Editors, Contributors) can upload files - this is required for exploitation
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Identify if thumbnail upload is permittedReview the media upload settings and confirm that thumbnail/image uploads are enabled for authenticated users. Test uploading an image file through the media library interface using a non-administrator accountAffected if Non-admin authenticated users can access the media upload functionality and add new images/thumbnails
You are affected if your WordPress installation is version 4.9.8 or earlier AND authenticated users (other than administrators) have permission to upload image files as thumbnails.
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 dataUpdate WordPress to the latest version to obtain the complete fix for this thumbnail processing vulnerability. If updating is not immediately possible, restrict thumbnail upload permissions to trusted users only until the patch can be applied.
Fix this in WordPress
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing6.0 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 $3,808.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-1000773 — 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-2018-1000773 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