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

MEDIUM 4.3CVE-2026-33527 · BIT-parse-2026-33527 · GHSA-jc39-686j-wp6q · Published 24/03/2026 · updated 17/06/2026

Package	Affected versions	Patched versions
parse-server parseplatform	`= 9.6.0≥ 9.0.0, < 9.6.0< 8.6.57`	`9.6.08.6.57`
parse-server npm	`≥ 9.0.0, < 9.6.0-alpha.48< 8.6.57`	`9.6.0-alpha.488.6.57`

Description

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

NVD description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0-alpha.48, 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. This issue has been patched in versions 8.6.57 and 9.6.0-alpha.48.

References

parse-community/parse-server security advisory · WEB
nvd.nist.gov/vuln/detail/CVE-2026-33527 · ADVISORY
parse-community/parse-server#10263 · WEB
parse-community/parse-server#10264 · WEB
parse-community/parse-server commit 26b628c · WEB
parse-community/parse-server commit ea68fc0 · WEB
parse-community/parse-server · PACKAGE

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Package

Affected versions

Patched versions

parse-server

parseplatform

= 9.6.0≥ 9.0.0, < 9.6.0< 8.6.57

9.6.08.6.57

parse-server

npm

≥ 9.0.0, < 9.6.0-alpha.48< 8.6.57

9.6.0-alpha.488.6.57

Description

Impact

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

NVD description