Parse Server's Session Update endpoint allows overwriting server-generated session fields

Impact

An authenticated user can overwrite server-generated session fields such as expiresAt and createdWith when updating their own session via the REST API. This allows bypassing the server's configured session lifetime policy, making a session effectively permanent.

Patches

The fix blocks authenticated users from setting expiresAt and createdWith fields when updating a session. Master key and maintenance key operations are not affected.

Workarounds

There is no known workaround other than upgrading.

Resources

• GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-jc39-686j-wp6q
• Fix Parse Server 9: https://github.com/parse-community/parse-server/pull/10263
• Fix Parse Server 8: https://github.com/parse-community/parse-server/pull/10264