CVE-2026-30870 json
Some sync filters in PowerSync Service ignored using `config.edition: 3`
published 8mo ago modified 4mo ago also GHSA-q6wc-xx4m-92fj , EUVD-2026-10416
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm @powersync/service-core 1.20.1
- npm @powersync/service-sync-rules 0.33.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @powersync/service-core | >=1.20.0, <1.20.1 |
1.20.1 |
| npm | @powersync/service-sync-rules | >=0.32.0, <0.33.0 |
0.33.0 |
Affected products
- powersync-ja powersync-service
- @powersync service-core
- @powersync service-sync-rules
Classification
- Weakness
-
- CWE-285 Improper Authorization
References
Sources
- CVE List CVE-2026-30870
- GitHub Advisory GHSA-q6wc-xx4m-92fj
- NVD CVE-2026-30870
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