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CVE-2026-35200 parse-community CVE debrief

CVE-2026-35200 is a vulnerability in Parse Server, an open-source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.73 and 9.7.1-alpha.4, a file can be uploaded with a filename extension that passes the file extension allowlist but with a Content-Type header that differs from the extension. This can lead to storage adapters serving the file with a mismatched Content-Type. The default GridFS adapter is not affected as it derives Content-Type from the filename at serving time.

Vendor
parse-community
Product
parse-server
CVSS
LOW 2.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-06
Original CVE updated
2026-07-24
Advisory published
2026-04-06
Advisory updated
2026-07-24

Who should care

Users of Parse Server, especially those hosting it on their own infrastructure, should be aware of this vulnerability. This issue could potentially allow attackers to serve files with incorrect Content-Types, which might lead to security issues such as incorrect handling of file types by clients or servers.

Technical summary

The vulnerability arises from the inconsistent validation of file extensions and Content-Type headers in file uploads. An attacker could exploit this by uploading a file with a permitted extension (e.g., .txt) but with a Content-Type header that indicates a different type (e.g., text/html). This discrepancy can be abused to serve files with incorrect Content-Types when using certain storage adapters like S3 or GCS. The issue is resolved in Parse Server versions 8.6.73 and 9.7.1-alpha.4.

Defensive priority

Low

Recommended defensive actions

  • Update Parse Server to version 8.6.73 or 9.7.1-alpha.4, or later.
  • Review file upload and serving configurations.
  • Monitor for unusual file upload activity.
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
  • Review compensating controls for exposed systems while remediation is scheduled and verified.
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review.
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record was published on 2026-04-06T20:16:27.720Z and was last modified on 2026-07-24T21:10:00.143Z. The NVD entry is currently Analyzed. Evidence is limited to public sources and may not reflect the full scope or details of the vulnerability. Defenders should verify the affected scope and vendor guidance through official channels.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-04-06T20:16:27.720Z and has not been modified since then. The NVD entry is currently Analyzed.