What is CVE-2026-30870?

CVE-2026-30870 is a medium-severity vulnerability in @Powersync Service-core, classified under Improper Authorization. CVSS score: 6.5/10. Published 2026-03-09.

How severe is CVE-2026-30870?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Auth bypass in @Powersync Service-core

CVE-2026-30870

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. Dependi…

EPSS: 0.000 (13.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

@Powersync Service-core — versions < 1.20.1
@Powersync Service-sync-rules — versions < 0.33.0
Powersync-ja Powersync-service — versions < 1.20.1

Weakness classification (CWE)

CWE-285 — Improper Authorization

References

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

Frequently asked questions

What is CVE-2026-30870?: CVE-2026-30870 is a medium-severity vulnerability in @Powersync Service-core, classified under Improper Authorization. CVSS score: 6.5/10. Published 2026-03-09.
How severe is CVE-2026-30870?: Medium severity. CVSS v3 base score is 6.5 out of 10.