CVE-2026-47735

Received Received - Intake

SQL Injection Risk in Arc Time-Series Database

Publication date: 2026-08-21

Last updated on: 2026-08-21

Assigner: GitHub, Inc.

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`.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-08-21

Last Modified

2026-08-21

Generated

2026-08-22

AI Q&A

2026-08-22

EPSS Evaluated

N/A

NVD

CVE-2026-47735

Affected Vendors & Products

Vendor	Product	Version / Range
arc	arc	26.06.1
duckdb	duckdb	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-22	The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
CWE-200	The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
CWE-918	The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Attack-Flow Graph

Executive Summary

This vulnerability in Arc, a SQL-native time-series database, involves insufficient input validation in its SQL query processing. The system only blocked specific dangerous functions like read_parquet( and arc_partition_agg( via a denylist regex, while other DuckDB I/O functions such as read_csv_auto, read_json, glob, and parquet_metadata remained accessible. Additionally, RBAC table-reference checks only examined FROM/JOIN clauses, allowing scalar table functions in SELECT lists to bypass security controls. This flaw enables unauthorized file access and potential data exfiltration through SQL injection.

Detection Guidance

This vulnerability involves insufficient blocking of DuckDB I/O functions in Arc's SQL validator. Detection requires checking Arc's configuration for exposed dangerousSQLPattern entries or reviewing SQL queries for use of functions like read_csv, read_json, glob, or parquet_metadata. No specific commands are provided in the context.

Impact Analysis

An attacker could exploit this to read sensitive files on the server, access unauthorized data, or perform lateral movement within the system. Since DuckDB functions can read various file formats, this includes configuration files, logs, or other sensitive data stored on the host. The impact depends on the Arc deployment's file permissions and network access.

Compliance Impact

This vulnerability likely violates compliance requirements for data protection regulations like GDPR and HIPAA, which mandate strict access controls and protection of personal or health data. Unauthorized file access could lead to data breaches, triggering mandatory breach notifications and potential fines under these regulations.

Mitigation Strategies

Upgrade Arc to version 26.06.1 or later to apply the structural sandbox fix at the DuckDB layer.
Temporarily add dangerous functions (e.g., read_csv*, read_json*, glob) to Arc's dangerSQLPattern in internal/api/query.go as a workaround.
Restrict API access to trusted networks using firewall rules to limit exposure.

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