CVE-2026-47735 Arc has an authenticated arbitrary local-file read via DuckDB I/O functions that bypasses RBAC table-level checks
Authenticated users can read arbitrary local files by bypassing SQL validation and RBAC checks using unblocked DuckDB I/O functions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-47735?
CVE-2026-47735 is a high-severity path traversal vulnerability in Basekick-Labs arc, published on 21 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Arc is an open, SQL-native time-series database for telemetry. Prior to version 26.06.1, Arc's user-SQL validator (`internal/api/query.go:ValidateSQLRequest`) blocked only `read_parquet(` and `arc_partition_agg(` via regex denylist. The broader DuckDB I/O function family — `read_csv_auto`, `read_csv`, `read_json`, `read_json_auto`, `read_text`, `read_blob`, `glob`, `parquet_metadata`, `parquet_schema`, `read_xlsx`, etc. — was not blocked. RBAC table-reference extraction inspected only `FROM`/`JOIN` clauses, so scalar table functions in the `SELECT` list slipped past both layers. This is fixed in 2026.06.1 via a structural sandbox at the DuckDB layer. After lockdown, DuckDB refuses to open any file outside the allowlist and refuses further `INSTALL`/`LOAD`. Already-loaded extensions remain callable. Some workarounds are available. Restrict API access to known-trusted networks via firewall rules or, as a temporary mitigation, add `read_csv*`/`read_json*`/`glob` etc. to `dangerousSQLPattern` in `internal/api/query.go`.
Which versions are affected by CVE-2026-47735?
3 open source packages ship an affected version, including github.com/basekick-labs/arc.
| Package | Affected | Fixed in |
|---|---|---|
github.com/basekick-labs/arc Go | All versions | 0.0.0-20260520141557-91bdc29d1a02 |
github.com/basekick-labs/arc Go | All versions | 0.0.0-20260520141557-91bdc29d1a02 |
github.com/basekick-labs/arc Go | All versions | 0.0.0-20260520141557-91bdc29d1a02 |
How do I fix CVE-2026-47735?
Upgrade github.com/basekick-labs/arc to 0.0.0-20260520141557-91bdc29d1a02 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-47735 being exploited?
There is no known exploitation of CVE-2026-47735 in the wild and no public exploit code.
Sources
Also known as GHSA-p2j4-c4g6-rpf5, GO-2026-5523.