Summary
Laravel Backpack CRUD: HasUploadFields keeps the attacker-supplied file extension, public-disk uploads of shell.php reach the webserver
HasUploadFields (used via CrudTrait on Backpack-managed models) and the withFiles() uploader preserve the client-supplied file extension without validation. On installations using a public disk with php artisan storage:link, this allows an authenticated administrator to upload a file with a server-executable extension that the web server will pass to the PHP interpreter - if no MIME or other type of upload validation is present.
Details
The uploadFileToDisk and uploadMultipleFilesToDisk methods hash the filename stem but write the client-supplied extension to disk verbatim, no allowlist, blocklist, or MIME check is applied inside the trait itself.
The newer withFiles() path (via FileNameGenerator) resolves the extension from the file's MIME type rather than the client filename, but also does not block server-executable types.
Applications that follow the Backpack quickstart without adding explicit mimes: or mimetypes: validation rules in their form requests are affected.
Recommended developer action
Review all upload fields and add explicit mimes: or mimetypes: validation in your form requests or field definitions. Refer to the Backpack field documentation for examples.
Reported by Vishal Shukla (@shukla304) via sechub.dev.
Impact
An authenticated administrator with access to an upload-enabled CRUD panel, on a site using the public disk with web-accessible storage and no MIME type validation, can upload a server-executable file and achieve remote code execution.
Conditions required for exploitation:
- Authenticated admin access to a Backpack CRUD panel
- An upload field with no
mimes:/mimetypes:validation rule - The
publicdisk in use (standard pattern for web-visible uploads) php artisan storage:linkin place- A web server + PHP-FPM stack (default on most hosts)
The application accepts file uploads without adequately restricting the file type or content. Typical impact: remote code execution if the uploaded file can be served and executed on the server.
CVE-2026-54177 has a CVSS score of 6.6 (Medium). The vector is network-reachable, high privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (6.8.14, 7.0.38); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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A denylist for server-executable extensions has been added to both HasUploadFields and FileNameGenerator. Image-typed fields now additionally enforce an allowlist. This is defence-in-depth, it does not replace application-level validation.
Frequently Asked Questions
- What is CVE-2026-54177? CVE-2026-54177 is a medium-severity unrestricted upload of dangerous file types vulnerability in backpack/crud (composer), affecting versions >= 6.0.0, < 6.8.14. It is fixed in 6.8.14, 7.0.38. The application accepts file uploads without adequately restricting the file type or content.
- How severe is CVE-2026-54177? CVE-2026-54177 has a CVSS score of 6.6 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of backpack/crud are affected by CVE-2026-54177? backpack/crud (composer) versions >= 6.0.0, < 6.8.14 is affected.
- Is there a fix for CVE-2026-54177? Yes. CVE-2026-54177 is fixed in 6.8.14, 7.0.38. Upgrade to this version or later.
- Is CVE-2026-54177 exploitable, and should I be worried? Whether CVE-2026-54177 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-54177 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-54177?
- Upgrade
backpack/crudto 6.8.14 or later - Upgrade
backpack/crudto 7.0.38 or later
- Upgrade