CVE-2026-30870

Some sync filters in PowerSync Service ignored using `config.edition: 3`

State: Published
Severity: 6.5 Medium
Published: Mar 9, 2026
Updated: Mar 10, 2026
Reserved: Mar 6, 2026

Description

PowerSync Service is the server-side component of the PowerSync sync engine. In version 1.20.0, when using new sync streams with config.edition: 3, certain subquery filters were ignored when determining which data to sync to users. Depending on the sync stream configuration, this could result in authenticated users syncing data that should have been restricted. Only queries that gate synchronization using subqueries without partitioning the result set are affected. This vulnerability is fixed in 1.20.1.

Scores

CVSS	Score	Vector	Source
3.1	6.5 Medium	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N	GitHub_M

Weaknesses

CWE-285 Improper Authorization

Affected Products

Product	Versions
powersync-servicepowersync-ja	< 1.20.1Affected
service-core@powersync	< 1.20.1Affected
service-sync-rules@powersync	< 0.33.0Affected

References

https://github.com/powersync-ja/powersync-service/security/advisories/GHSA-q6wc-xx4m-92fj

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.