CVE intelligence and bounded remediation

CVE-2026-30948 — Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js

High CVSS 8.3

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.2-alpha.4 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-alpha.4 and 8.6.17.

Severity
High
CVSS
8.3 (4.0)
Published
2026-03-10
CISA KEV
Not currently listed
Ecosystem
javascript/npm
Weaknesses
CWE-79

Affected products

  • parseplatform / parse-server
  • parseplatform / parse-server / 9.5.2

Showing 2 representative product identities from 5 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Cross-site scripting and unsafe browser output

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace reflected, stored, and DOM-derived untrusted values into HTML, attributes, URLs, styles, scripts, and client-side template sinks.
  • Identify affected origins, authenticated user roles, sensitive browser capabilities, and where content is shared across tenants.
  • Review framework escaping, rich-text sanitization, legacy templates, and client-side rendering paths.

Remediate safely

  • Use context-aware framework output encoding and safe DOM APIs; keep untrusted data out of executable contexts.
  • Sanitize intentionally supported markup with a maintained allowlist policy and validate URLs and attributes separately.
  • Update affected rendering components and add tests for every output context using inert sentinel markup.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.