Parse Server is affected by a stored cross-site scripting (XSS) vulnerability in versions >= 9.0.0, < 9.10.0-alpha.2 and <= 8.6.83. When an uploaded file's extension is not recognized by the mime package, Parse Server preserves the client-supplied Content-Type. A malformed Content-Type that is not a valid type/subtype media type (e.g., 'image', 'image/', or 'image//svg+xml') bypasses the fileUpload.fileExtensions blocklist and is stored unchanged. On storage adapters that persist and serve the uploaded Content-Type (such as Amazon S3, Google Cloud Storage, or Azure Blob Storage), a browser cannot parse the malformed value and falls back to MIME-sniffing; a file whose body begins with HTML is rendered as HTML, executing embedded script in the application's origin against other users who open the file URL. The default GridFS storage adapter is not affected. Fixed in 9.10.0-alpha.2 and 8.6.84.

Project Subscriptions

Vendors Products
Parse Community Subscribe
Parse Server Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Sat, 11 Jul 2026 15:30:00 +0000

Type Values Removed Values Added
First Time appeared Parse Community
Parse Community parse Server
Vendors & Products Parse Community
Parse Community parse Server

Sat, 11 Jul 2026 13:30:00 +0000

Type Values Removed Values Added
Description Parse Server is affected by a stored cross-site scripting (XSS) vulnerability in versions >= 9.0.0, < 9.10.0-alpha.2 and <= 8.6.83. When an uploaded file's extension is not recognized by the mime package, Parse Server preserves the client-supplied Content-Type. A malformed Content-Type that is not a valid type/subtype media type (e.g., 'image', 'image/', or 'image//svg+xml') bypasses the fileUpload.fileExtensions blocklist and is stored unchanged. On storage adapters that persist and serve the uploaded Content-Type (such as Amazon S3, Google Cloud Storage, or Azure Blob Storage), a browser cannot parse the malformed value and falls back to MIME-sniffing; a file whose body begins with HTML is rendered as HTML, executing embedded script in the application's origin against other users who open the file URL. The default GridFS storage adapter is not affected. Fixed in 9.10.0-alpha.2 and 8.6.84.
Title Parse Server 9.0.0 Stored XSS via malformed Content-Type
Weaknesses CWE-434
References
Metrics cvssV4_0

{'score': 2.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-07-11T13:01:05.852Z

Reserved: 2026-07-09T14:06:14.016Z

Link: CVE-2026-61448

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-11T15:15:05Z

Weaknesses