CVE-2026-30948
March 10, 2026
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.
Affected Packages
https://github.com/parse-community/parse-server.git (GITHUB):
Affected version(s) >=9.0.0 <9.5.2-alpha.4Fix Suggestion:
Update to version 9.5.2-alpha.4https://github.com/parse-community/parse-server.git (GITHUB):
Affected version(s) >=2.0.0 <8.6.17Fix Suggestion:
Update to version 8.6.17parse-server (NPM):
Affected version(s) >=1.0.0 <8.6.17Fix Suggestion:
Update to version 8.6.17parse-server (NPM):
Affected version(s) >=9.0.0 <9.5.2-alpha.4Fix Suggestion:
Update to version 9.5.2-alpha.4Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
PASSIVE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
HIGH
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.8
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
EPSS
Base Score:
0.02
