Medium (4.3) in parseplatform parse-server. EPSS 0.3% chance of exploitation in the next 30 days. Fixed in parse-server 8.6.42, 9.6.0-alpha.17.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.6.0-alpha.17 and 8.6.42, an authenticated user can overwrite server-generated session fields (`sessionToken`, `expiresAt`, `createdWith`) when creating a session object via `POST /classes/_Session`. This allows bypassing the server's session expiration policy by setting an arbitrary far-future expiration date. It also allows setting a predictable session token value. Starting in version 9.6.0-alpha.17 and 8.6.42, the session creation endpoint filters out server-generated fields from user-supplied data, preventing them from being overwritten. As a workaround, add a `beforeSave` trigger on the `_Session` class to validate and reject or strip any user-supplied values for `sessionToken`, `expiresAt`, and `createdWith`.
Severity
CVSS 3.1
4.3 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
EPSS
0.3% chance of exploitation in the next 30 days; higher than 24% of CVEs (scores of 2026-10-31)