CVE-2026-39321

Parse Server before 8.6.109 and 9.0.0 before 9.10.6-alpha.1 returns stored field values in object update responses without checking read access. Clients whose class-level permissions or object ACLs allow update but not read can see object data, including atomic operation results, Cloud Code trigger-set values, and whole parent fields under dot notation in certain conditions.

Parse Server from 9.7.0 before 9.10.5-alpha.10 contains an authorization flaw that applies _Installation updates addressed by object ID to the installation named in the X-Parse-Installation-Id header. When protectedFieldsTriggerExempt is enabled, attackers knowing another installation's object ID can make a beforeSave trigger process that installation's protected fields while writing elsewhere.

Parse Server prior to versions 8.6.67 and 9.7.0-alpha.11 has a vulnerability where an attacker can bypass Cloud Function validator access controls by appending "prototype.constructor" to the function name in the URL. This causes all access control enforcement to be skipped, allowing unauthenticated callers to invoke protected Cloud Functions.

Parse Server prior to versions 8.6.3 and 9.1.1-alpha.4 is vulnerable to an attack where an unauthenticated attacker can forge a Google authentication token with 'alg: "none"', allowing them to log in as any user linked to a Google account without knowing their credentials.

Parse Server is an open source backend that can be deployed to any infrastructure that runs Node.js. In versions prior to 8.6.0-alpha.2, a GitHub CI workflow is triggered in a way that grants the GitHub Actions workflow elevated permissions, giving it access to GitHub secrets and write permissions which are defined in the workflow. Code from a fork or lifecycle scripts is potentially included. Only the repository's CI/CD infrastructure is affected, including any public GitHub forks with GitHub Actions enabled. This issue is fixed in version 8.6.0-alpha.2 and commits 6b9f896 and e3d27fe.

Parse Server prior to versions 5.5.2 and 6.2.1 is vulnerable to prototype pollution, which can lead to remote code execution through the MongoDB BSON parser.

Parse Server from 9.7.0 before 9.10.5-alpha.7 contains an information disclosure vulnerability that allows clients to receive protected field values written by beforeSave triggers using dot notation keys. When protectedFieldsSaveResponseExempt is set to false, clients with create or update permission can read values a trigger writes beneath a protected field in the same request.

Parse Server before 8.6.108 and 9.0.0 before 9.10.5-alpha.9 contains a prototype pollution vulnerability because user-controlled keys are expanded into objects without own-property checks. Clients with class write access can send dot notation field keys or ACL entry names matching built-in object members to corrupt built-in functions, causing all requests to fail until server restart.

Parse Server before 8.6.106 and 9.0.0 before 9.10.5-alpha.7 mishandles dot notation keys with null or undefined values when building the saved object, so a write is stored but returns an error and skips afterSave triggers and LiveQuery events. A client with write access can exploit this to evade audit logging, notifications, and derived data updates.

Parse Server before 8.6.107 and 9.0.0 before 9.10.5-alpha.8 returns the stored value of a field reverted by a beforeSave trigger in object update responses, even to clients without read access to that object or field. An authenticated client able to update an object whose beforeSave trigger reverts a field, via revert() or a constant: true validator, can read protected values, including its own account's raw MFA authData when protectedFieldsTriggerExempt is enabled.