The Twig content sandbox fails to restrict dump and serialize filters, specifically `print r`, `vardump`, `json encode`, `yaml encode`, and `string`. This occurs because the `GravExtension::assertSandboxDumpSafe()` function calls `SandboxExtension::isSandboxed()` without a `Source` argument, which only reports a global sandbox flag that is never enabled. Consequently, an authenticated user with page-edit rights can use Twig processing in page content to dump the entire merged configuration. This bypasses path redaction in the `SandboxConfig` facade and exposes sensitive plugin secrets, including SMTP credentials, API tokens, webhook secrets, and cache backend passwords.