PostgreSQL
TMA-POSTGRES-4.5
Ensure excessive function privileges are revoked
Description
In certain situations, to provide the required functionality, PostgreSQL needs to execute internal logic (stored procedures, functions, triggers, etc.) and/or external code modules with elevated privileges. Counts SECURITY DEFINER functions outside pg_catalog/information_schema that are not owned by an extension, in the database it connects to (set PGDATABASE to check each database); accept justified functions as exceptions. Runs psql as ${PGUSER:-postgres} against ${PGDATABASE:-postgres}; set PGHOST/PGPORT and use ~/.pgpass (not PGPASSWORD, see 1.6/1.7) when peer authentication is not available.
How it is checked
Audit method: SQL query
out=$(psql -X -U "${PGUSER:-postgres}" -d "${PGDATABASE:-postgres}" -tAc "SELECT count(*) FROM pg_proc p JOIN pg_namespace n ON n.oid = p.pronamespace WHERE p.prosecdef AND n.nspname NOT IN ('pg_catalog','information_schema') AND p.proname NOT LIKE 'pgaudit%' AND NOT EXISTS (SELECT 1 FROM pg_depend d WHERE d.classid = 'pg_proc'::regclass AND d.objid = p.oid AND d.deptype = 'e')" 2>/dev/null) || exit 1; printf '%s\n' "$out"- Expected output
0
How it is fixed
Fix method: Guidance or infrastructure patch
Review each SECURITY DEFINER function; switch it with ALTER FUNCTION <name>(<args>) SECURITY INVOKER; or, if elevation is required, REVOKE EXECUTE ON FUNCTION <name>(<args>) FROM PUBLIC/<roles> so only the accounts that need it can run it.
Properties
- Operating systems
- Any
- Tags
- postgresdatabaseauthorization
- Reference
- CIS PostgreSQL 18 Benchmark v1.0.0 - 4.5 Ensure excessive function privileges are revoked
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target postgres