Phishing attack vulnerability by uploading malicious HTML fileGHSA-9prm-jqwx-45x9
MEDIUMFix: parse-community/parse-server#8537GHSA-9prm-jqwx-45x9 is a medium-severity (CVSS 6.3) Unrestricted File Upload vulnerability in parse-server. A fix is available for parse-server — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-9prm-jqwx-45x9.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
parse-server📦parse-serverReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Phishing attack vulnerability by uploading malicious files. A malicious user could upload a HTML file to Parse Server via its public API. That HTML file would then be accessible at the internet domain at which Parse Server is hosted. The URL of the the uploaded HTML could be shared for phishing attacks. The HTML page may seem legitimate because it is served under the internet domain where Parse Server is hosted, which may be the same as a company's official website domain.
An additional security issue arises when the Parse JavaScript SDK is used. The SDK stores sessions in the internet browser's local storage, which usually restricts data access depending on the internet domain. A malicious HTML file could contain a script that retrieves the user's session token from local storage and then share it with the attacker.
Patches
The fix adds a new Parse Server option fileUpload.fileExtensions to restrict file upload on Parse Server by file extension. It is recommended to restrict file upload for HTML file extensions, which this fix disables by default. If an app requires upload of files with HTML file extensions, the option can be set to ['.*'] or another custom value to override the default.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | all versions | 5.4.4npm install parse-server@5.4.4 |
| 📦npm | parse-server | ≥ 6.0.0&&< 6.1.1 | 6.1.1npm install parse-server@6.1.1 |
Affected Products
parse-serverparseplatformDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update parse-server to 5.4.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9prm-jqwx-45x9 is resolved across your whole dependency graph.
Workarounds
Treat uploaded files as untrusted until proven otherwise: validate the actual content type rather than the supplied extension, store uploads outside the web root on a volume mounted without execute permission, and rename them to server-generated identifiers so an attacker cannot choose the path a request will later resolve.
Frequently Asked Questions
Is GHSA-9prm-jqwx-45x9 in your dependencies?
Find it across npm, including transitive dependencies.