CVE-2026-6847
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 · uneditedRemote Code Execution vulnerability exists in ThemisNETPanel due to missing authentication for a critical file upload function. The application exposes an endpoint that allows unauthenticated attackers to upload arbitrary PHP files by providing a base64-encoded payload and to execute arbitrary code on the underlying server. This issue has been fixed by a patch released in April 2026.
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 confidenceThemisNETPanel contains a critical authentication bypass vulnerability in its file upload functionality. The application exposes an endpoint that accepts base64-encoded PHP payloads without requiring authentication, allowing remote attackers to upload and execute arbitrary code on the server.
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
- None
- Authentication
- X
- User interaction
- None
- Scope
- X
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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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Confirm ThemisNETPanel installationSearch for ThemisNETPanel in your application inventory, check running services, or look for the product in your web server's document root directories.Affected if ThemisNETPanel is found running in your environment
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Identify installed versionCheck the application's about page, version file, or headers returned by the web server. Compare against any version information you can obtain from the vendor.Affected if The installed version is unknown or falls within an unpatched range
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Verify file upload endpoint exposureLocate the file upload functionality in the web application. Common paths may include /upload, /file/upload, or similar endpoints. Attempt to access these endpoints without providing credentials.Affected if The file upload endpoint responds without requiring authentication
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Test for base64-encoded payload acceptanceSend a request to the upload endpoint with a base64-encoded PHP payload (e.g., a simple test like <?php phpinfo(); ?> encoded in base64) without any authentication headers or session cookies.Affected if The endpoint accepts and processes the base64-encoded payload without authentication, returning a successful upload response
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Check for webshell artifactsSearch the web root directory for newly created PHP files, especially in upload directories. Review access logs for unusual POST requests to upload endpoints from unauthorized IP addresses.Affected if Unexpected PHP files exist in upload directories or logs show unauthenticated upload attempts
Your environment is affected if ThemisNETPanel is installed with an unpatched version and the file upload endpoint is accessible without authentication.
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 dataApply the vendor patch released in April 2026 immediately. If patching is not possible immediately, disable or restrict access to the file upload endpoint at the network level until the fix can be deployed.
- Consultation2.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA3.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2026-6847 — 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-2026-6847 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
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