CVE-2026-42031: CKAN SQL Injection Vulnerability

CVE-2026-42031 Overview

CKAN is an open-source data management system (DMS) used to power data hubs and data portals. A SQL injection vulnerability [CWE-89] exists in the datastore_search_sql function in CKAN versions prior to 2.10.10 and 2.11.5. Attackers can inject SQL statements through this function to gain unauthorized access to private resources and PostgreSQL system information. The flaw is exploitable remotely over the network without authentication. CKAN maintainers fixed the vulnerability in versions 2.10.10 and 2.11.5.

Critical Impact

Unauthenticated attackers can execute arbitrary SQL queries against the underlying PostgreSQL database, exposing private dataset contents and database system metadata.

Affected Products

• CKAN versions prior to 2.10.10
• CKAN versions prior to 2.11.5
• Any data portal or data hub deployment using the datastore_search_sql API endpoint

Discovery Timeline

• 2026-05-13 - CVE-2026-42031 published to NVD
• 2026-05-13 - Last updated in NVD database

Technical Details for CVE-2026-42031

Vulnerability Analysis

The vulnerability resides in CKAN's datastore_search_sql API action. This endpoint accepts a SQL query string and executes it against the PostgreSQL datastore backing CKAN. Input sanitization and query validation are insufficient to prevent attacker-controlled SQL from reaching the database engine.

An attacker can craft a query that bypasses the access control logic intended to restrict reads to public resources. Successful exploitation grants read access to private datasets and to PostgreSQL system catalogs such as pg_catalog and information_schema. This exposes table structures, role names, and other database metadata that aid further attacks.

The issue is classified as [CWE-89] Improper Neutralization of Special Elements used in an SQL Command. The attack vector is network-based, requires no authentication, and requires no user interaction.

Root Cause

The datastore_search_sql function fails to properly neutralize SQL syntax constructs supplied by remote clients. CKAN's filtering logic, which is intended to constrain the query to permitted resources, can be circumvented by crafted SQL input. The resulting query is passed to PostgreSQL with attacker-controlled clauses intact.

Attack Vector

An unauthenticated attacker sends a crafted request to the CKAN datastore_search_sql API endpoint. The injected SQL allows the attacker to read rows from private resources stored in the datastore and to query PostgreSQL system tables. No authentication, privileged role, or local access is required. Refer to the CKAN GitHub Security Advisory GHSA-h7j7-3rx6-xvcg for technical details on the affected query path.

Detection Methods for CVE-2026-42031

Indicators of Compromise

• Requests to /api/3/action/datastore_search_sql containing SQL keywords such as UNION, pg_catalog, information_schema, or nested SELECT statements outside expected query patterns.
• Unexpected PostgreSQL query log entries referencing system catalogs originating from the CKAN service account.
• Spikes in datastore_search_sql API traffic from a single IP or user agent.

Detection Strategies

• Inspect web server and reverse proxy logs for POST and GET requests to datastore_search_sql with abnormally long or syntactically complex SQL payloads.
• Enable PostgreSQL log_statement = 'all' temporarily to capture queries issued by CKAN and review them for access to pg_catalog, pg_user, or private dataset tables.
• Deploy a web application firewall (WAF) rule that flags SQL injection patterns directed at the CKAN datastore API.

Monitoring Recommendations

• Alert on any access from the CKAN database role to PostgreSQL system catalogs that is not part of normal application behavior.
• Track failed and successful authentication-less API calls to datastore_search_sql and correlate with downstream database errors.
• Monitor outbound data volumes from the CKAN host for signs of bulk data exfiltration.

How to Mitigate CVE-2026-42031

Immediate Actions Required

• Upgrade CKAN to version 2.10.10 or 2.11.5, depending on the deployed major release branch.
• Audit PostgreSQL logs for evidence of prior exploitation, focusing on queries that access private resources or system catalogs.
• Rotate any credentials, API tokens, or secrets that may have been exposed through compromised private datasets.

Patch Information

The vulnerability is fixed in CKAN 2.10.10 and CKAN 2.11.5. Operators should apply the official upgrade as documented in the CKAN GitHub Security Advisory GHSA-h7j7-3rx6-xvcg. Verify the running version after upgrade using the CKAN CLI or the /api/3/action/status_show endpoint.

Workarounds

• Disable the datastore_search_sql API action in CKAN configuration if upgrading is not immediately possible.
• Restrict access to the CKAN datastore API at the reverse proxy or WAF layer to known, trusted IP ranges.
• Restrict the PostgreSQL role used by the CKAN datastore reader to the minimum required tables and revoke access to system catalogs where feasible.

# Configuration example: disable datastore_search_sql in ckan.ini
ckan.datastore.sqlsearch.enabled = false