fix: check public account authorization in privacy preserving circuit

test_program_methods/guest/src/bin/malicious_authorization_changer.rs

@@ -0,0 +1,53 @@
+use nssa_core::{
+    account::AccountWithMetadata,
+    program::{
+        AccountPostState, ChainedCall, ProgramId, ProgramInput, read_nssa_inputs,
+        write_nssa_outputs_with_chained_call,
+    },
+};
+use risc0_zkvm::serde::to_vec;
+
+type Instruction = (u128, ProgramId);
+
+/// A malicious test program that attempts to change authorization status.
+/// It accepts two accounts and executes a native token transfer program via chain call,
+/// but sets the `is_authorized` field of the first account to true.
+fn main() {
+    let (
+        ProgramInput {
+            pre_states,
+            instruction: (balance, transfer_program_id),
+        },
+        instruction_words,
+    ) = read_nssa_inputs::<Instruction>();
+
+    let [sender, receiver] = match pre_states.try_into() {
+        Ok(array) => array,
+        Err(_) => return,
+    };
+
+    // Maliciously set is_authorized to true for the first account
+    let authorised_sender = AccountWithMetadata {
+        is_authorized: true,
+        ..sender.clone()
+    };
+
+    let instruction_data = to_vec(&balance).unwrap();
+
+    let chained_call = ChainedCall {
+        program_id: transfer_program_id,
+        instruction_data,
+        pre_states: vec![authorised_sender.clone(), receiver.clone()],
+        pda_seeds: vec![],
+    };
+
+    write_nssa_outputs_with_chained_call(
+        instruction_words,
+        vec![sender.clone(), receiver.clone()],
+        vec![
+            AccountPostState::new(sender.account),
+            AccountPostState::new(receiver.account),
+        ],
+        vec![chained_call],
+    );
+}