backpack/crud security advisory

CVE-2026-54179: Laravel Backpack CRUD: SingleBase64Image accepts any base64 payload behind a data:image prefix — SVG-with-script lands on the public disk

CVE-2026-54179 is a medium-severity stored XSS vulnerability in the PHP package backpack/crud (CVSS 4.4), published 31 August 2026. It is fixed in 6.8.14 and 7.0.38, one per release line; earlier versions on each line are affected. Exploiting it needs a low-privilege user account.

medium 4.4 published 2026-08-31 · updated 2026-09-08

Affected versions: >= 6.0.0, < 6.8.14
>= 7.0.0, < 7.0.38
Fixed in: 6.8.14, 7.0.38
Newest release: 7.1.24
Severity: Medium · CVSS 4.4
Type: Stored cross-site scripting (XSS)
CWE-79, CWE-434
Exploited in the wild: Not on the CISA KEV list
checked 2026-11-04

Is your backpack/crud version affected?

Run composer show backpack/crud in your project, then enter the version. We check it against this and every other known backpack/crud advisory.

Who can exploit CVE-2026-54179

Access: A normal, low-privilege user account in the app.
Interaction: A user also has to do something, such as open a link or a page the attacker prepared.
Conditions: It only works under specific conditions the attacker does not fully control (CVSS rates the attack as high complexity).

CVSS vector (scored by GitHub): CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N

Your app is only exposed if it uses the affected part of backpack/crud. The advisory below says which part that is. If you are not sure, upgrade anyway: it costs less than finding out.

How to fix CVE-2026-54179 in backpack/crud

Find the installed version: composer show backpack/crud. If you never required it yourself, composer why backpack/crud shows which package pulls it in.
Update it: composer update backpack/crud --with-all-dependencies. You need the fixed version for your release line (6.8.14 and 7.0.38).
If Composer will not go that high, your composer.json constraint is holding it back. Widen it (for example "backpack/crud": "^7.0.38" if you can take that version), or upgrade the package that requires it.
Run composer audit. It reads the same advisory data and should no longer list CVE-2026-54179.
Commit composer.lock and deploy it. On the server, run composer install --no-dev from the lock file, not composer update.

If you cannot upgrade yet

General hardening for stored XSS issues while the upgrade waits. None of it replaces the fix.

Escape output in your own templates and add a Content-Security-Policy that blocks inline scripts.
Limit who can save the content the advisory names (for example rich text, SVG or form fields).
If your app does not use the affected feature, note that in your audit, but still plan the upgrade.

The CVE-2026-54179 advisory

backpack/crud provides Create, Read, Update & Delete (CRUD) functions for Backpack, a collection of Laravel packages that help users build custom administration panels. From 6.0.0 until 6.8.14 and 7.0.37, the src/app/Library/Uploaders/SingleBase64Image.php methods SingleBase64Image::uploadFiles and SingleBase64Image::uploadRepeatableFiles, used by image fields through withFiles(), accept any data URI beginning with data:image without validating the declared MIME subtype or decoded bytes, while src/app/Library/Uploaders/Support/FileNameGenerator.php method FileNameGenerator::getExtensionFromFile applies mime_content_type() to the data URI instead of the decoded content. An authenticated administrator can therefore store arbitrary file content under an extensionless filename on the configured disk, which can cause stored cross-site scripting or other unintended behavior when the file is served and accessed. This issue is fixed in version 7.0.38 and 6.8.14.

Description from the CVE record, published by GitHub (the CVE Numbering Authority), via the NVD entry for CVE-2026-54179. Advisory title: “Laravel Backpack CRUD: SingleBase64Image accepts any base64 payload behind a data:image prefix — SVG-with-script lands on the public disk”.

References

GitHub advisory GHSA-8hw4-7qjr-3wxg github.com
Fix commit 18b3dc1 github.com
Pull request #5989 github.com
Release 6.8.14 github.com
Release 7.0.38 github.com

Other backpack/crud advisories

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Where this data comes from

Affected and fixed versions: the Packagist security advisories API (GitHub Advisory Database and FriendsOfPHP), the same data composer audit uses. Synced 2026-11-03.
Description, score, weakness and references: NIST National Vulnerability Database (NVD), checked 2026-11-04. This product uses data from the NVD API but is not endorsed or certified by the NVD.
Exploited-in-the-wild status: the CISA Known Exploited Vulnerabilities catalog, checked 2026-11-04.
Compiled by Daniel Lasek at Laskyr from the sources above. The summary, “who can exploit it”, “how to fix it” and hardening sections are our plain-English reading of the record and are generated from it. The quoted description is the record's own text. Spot an error? Tell us.