CVE-2026-30948

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.2 and 8.6.17, a stored cross-site scripting (XSS) vulnerability allows any authenticated user to upload an SVG file containing JavaScript. The file is served inline with Content-Type: image/svg+xml and without protective headers, causing the browser to execute embedded scripts in the Parse Server origin. This can be exploited to steal session tokens from localStorage and achieve account takeover. The default fileExtensions option blocks HTML file extensions but does not block SVG, which is a well-known XSS vector. All Parse Server deployments where file upload is enabled for authenticated users (the default) are affected. This vulnerability is fixed in 9.5.2 and 8.6.17.

How to fix CVE-2026-30948

To remediate CVE-2026-30948, upgrade the affected package to a fixed version below.

• —upgrade to 8.6.17 or later
• —upgrade to 9.5.2-alpha.4 or later

Is CVE-2026-30948 being exploited?

Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 8.6.17, >= 9.0.0, < 9.5.2
• >= 9.0.0, < 9.5.2-alpha.4

CVSS scores

References (5)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2026-30948
• PATCHgithub.com/parse-community/parse-server
• WEBgithub.com/parse-community/parse-server/releases/tag/8.6.17
• WEBgithub.com/parse-community/parse-server/releases/tag/9.5.2-alpha.4