CVE-2026-22707: Strapi is an open source headless content management system. In Strapi versions prior to 5.33.3, the Upload plugin's Content API endpoints did not enf...

Description

Strapi is an open source headless content management system. In Strapi versions prior to 5.33.3, the Upload plugin's Content API endpoints did not enforce the administrator-configured MIME type restrictions (`plugin.upload.security.allowedTypes` and `deniedTypes`). The same restrictions were correctly enforced on the Admin Panel upload path. The upload plugin's `enforceUploadSecurity` security check was invoked in the admin upload controller but was missing from the Content API controller. The Content API handlers `uploadFiles` and `replaceFile` (and the `upload` wrapper that dispatches to them) called the underlying upload service directly, bypassing both the magic-byte MIME detection and the configured allow/deny lists. An authenticated user with the Content API upload permission could therefore upload file types the administrator had explicitly disallowed, including HTML and SVG content. In deployments serving uploaded files from the same origin as the admin panel (default), an attacker could upload an HTML or SVG file that, when opened directly by an admin, executed JavaScript in the admin origin, enabling admin-session hijack and authenticated administrative actions against the admin API. The patch in version 5.33.3 introduces a shared `prepareUploadRequest` helper that wraps `enforceUploadSecurity` and is called from both the Content API and admin upload controllers, ensuring identical security policy enforcement on every upload entry point.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

CVSS 4.0

5.3/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/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

EPSS Probability

0.19%

9.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Strapi	Strapi	< 5.33.3

References

https://github.com/strapi/strapi/security/advisories/GHSA-pcw7-5633-82vvVendor Advisory

Timeline

Published: May 14, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-22707?

Strapi is an open source headless content management system. In Strapi versions prior to 5.33.3, the Upload plugin's Content API endpoints did not enforce the administrator-configured MIME type restrictions (`plugin.upload.security.allowedTypes` and `deniedTypes`). The same restrictions were correctly enforced on the Admin Panel upload path. The upload plugin's `enforceUploadSecurity` security check was invoked in the admin upload controller but was missing from the Content API controller. The Content API handlers `uploadFiles` and `replaceFile` (and the `upload` wrapper that dispatches to them) called the underlying upload service directly, bypassing both the magic-byte MIME detection and the configured allow/deny lists. An authenticated user with the Content API upload permission could therefore upload file types the administrator had explicitly disallowed, including HTML and SVG content. In deployments serving uploaded files from the same origin as the admin panel (default), an attacker could upload an HTML or SVG file that, when opened directly by an admin, executed JavaScript in the admin origin, enabling admin-session hijack and authenticated administrative actions against the admin API. The patch in version 5.33.3 introduces a shared `prepareUploadRequest` helper that wraps `enforceUploadSecurity` and is called from both the Content API and admin upload controllers, ensuring identical security policy enforcement on every upload entry point.

How severe is CVE-2026-22707?

CVE-2026-22707 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.19% probability of exploitation in the next 30 days.

How do I fix CVE-2026-22707?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.