CVE-2026-42087: OpenC3 COSMOS has SQL Injection in QuestDB Time-Series Database

Vulnerability Type: CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') Attack type: Authenticated remote Impact: Telemetry data disclosure and deletion Affected components: openc3-tsdb (QuestDB)

A SQL injection vulnerability exists in the Time-Series Database (TSDB) component of COSMOS. The tsdb_lookup function in the cvt_model.rb file directly places user-supplied input into a SQL query without sanitizing the input. As a result, a user can break out of the initial SQL statement and execute arbitrary SQL commands, including deleting data.

Figure 1: Source code vulnerable to SQL injection Additionally, the get_tlm_values RPC endpoint only requires “tlm” permissions, allowing any user with the Admin, Operator, Viewer, or Runner roles to send a request to the TSDB. This permission is defined in roles-permissions.md to allow for the user to view telemetry data, but this vulnerability also allows them to delete data and tables.

Figure 2: Source code showing the required permissions for the get_tlm_values endpoint Sending a normal request to the endpoint brings back a single array of values for the parameter:

Figure 3: A normal request to the get_tlm_values endpoint However, sending a specially crafted request within the start_time variable brings back all the data in the database:

Figure 4: The request and response after sending the SQL injection payload This payload can be modified to executes SQL commands in the TSDB.

Figure 5: SQL injection used to execute arbitrary SQL command The user can then delete all the historical data in the database:

Figure 6: Example payload dropping the tables

Steps to Reproduce

1. Capture a JSON-RPC request to the get_tlm_values endpoint.
2. Add the start_time key to the request body and place the following in the value:

‘ OR 1=1 --

1. Retrieve all database data.

Recommendations

• Sanitize all user-supplied input before executing it • Use prepared statements with parameterized queries when executing SQL statements