VDB
KO
MEDIUM

GHSA-j7mm-f4rv-6q6q

Parse Server has a protected fields bypass via LiveQuery subscription WHERE clause

Details

### Impact

An attacker can exploit LiveQuery subscriptions to infer the values of protected fields without directly receiving them. By subscribing with a WHERE clause that references a protected field (including via dot-notation or `$regex`), the attacker can observe whether LiveQuery events are delivered for matching objects. This creates a boolean oracle that leaks protected field values. The attack affects any class that has both `protectedFields` configured in Class-Level Permissions and LiveQuery enabled.

### Patches

The fix adds validation of the LiveQuery subscription WHERE clause against the class's protected fields, mirroring the existing REST API validation. If a subscription's WHERE clause references a protected field directly, via dot-notation, or inside `$or` / `$and` / `$nor` operators, the subscription is rejected with a permission error. This is applied during subscription creation, so existing event delivery paths are not affected.

### Workarounds

Disable LiveQuery for classes that use `protectedFields` in their Class-Level Permissions, or remove `protectedFields` from classes that require LiveQuery.

### References

- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-j7mm-f4rv-6q6q - Fix Parse Server 9: https://github.com/parse-community/parse-server/releases/tag/9.6.0-alpha.9 - Fix Parse Server 8: https://github.com/parse-community/parse-server/releases/tag/8.6.35

Are you affected?

Enter the version of the package you're using.

Affected packages

npm / parse-server
Introduced in: 9.0.0 Fixed in: 9.6.0-alpha.9
Fix npm install parse-server@9.6.0-alpha.9
npm / parse-server
Introduced in: 0 Fixed in: 8.6.35
Fix npm install parse-server@8.6.35

References