Active Boosts

#37661 [SC-High] Incorrect `total_active_stake` reduction causes loss of funds for the users and excessive fees collection over time

Submitted on Dec 11th 2024 at 22:09:38 UTC by @holydevoti0n for Audit Comp | Folks: Liquid Staking

  • Report ID: #37661

  • Report Type: Smart Contract

  • Report severity: High

  • Target: https://github.com/Folks-Finance/algo-liquid-staking-contracts/blob/8bd890fde7981335e9b042a99db432e327681e1a/contracts/xalgo/consensus_v2.py

  • Impacts:

    • Permanent freezing of funds

    • Permanent freezing of unclaimed yield

Description

Brief/Intro

The burn operation incorrectly reduces total_active_stake by including rewards in the reduction amount. This leads to inflated reward calculations, causing the protocol to collect excessive fees from user funds.

Vulnerability Details

When users burn xALGO, the contract incorrectly reduces total_active_stake by the full withdrawal amount (stake + rewards): https://github.com/Folks-Finance/algo-liquid-staking-contracts/blob/8bd890fde7981335e9b042a99db432e327681e1a/contracts/xalgo/consensus_v2.py#L824

def burn(send_xalgo: abi.AssetTransferTransaction, min_received: abi.Uint64) -> Expr:
    burn_amount = send_xalgo.get().asset_amount()
    algo_balance = ScratchVar(TealType.uint64)
    algo_to_send = ScratchVar(TealType.uint64)

    return Seq(
        # calculate algo amount to send
@>        algo_balance.store(
            App.globalGet(total_active_stake_key)
@>            + App.globalGet(total_rewards_key)
            - App.globalGet(total_unclaimed_fees_key)
        ),
@>        algo_to_send.store(
            mul_scale(
                burn_amount,
                algo_balance.load(),
                get_x_algo_circulating_supply() + burn_amount
            )
        ),
       ...
        # update total active stake
@>        App.globalPut(total_active_stake_key, App.globalGet(total_active_stake_key) - algo_to_send.load()),
        ...
    )

  1. First burn distorts total_active_stake by including rewards in reduction.

  2. Subsequent burns use this distorted total_active_stake value.

  3. Creates compounding error where each burn further distorts the rate.

The second problem is that the total_active_stake is used to calculate the protocol fees and the total in rewards: https://github.com/Folks-Finance/algo-liquid-staking-contracts/blob/8bd890fde7981335e9b042a99db432e327681e1a/contracts/xalgo/consensus_v2.py#L144-L147

def update_total_rewards_and_unclaimed_fees():
    old_total_rewards = ScratchVar(TealType.uint64)
    new_total_rewards = ScratchVar(TealType.uint64)

    return Seq(
        # update total rewards
        old_total_rewards.store(App.globalGet(total_rewards_key)),
        new_total_rewards.store(get_proposers_algo_balance(Int(0)) - App.globalGet(total_pending_stake_key) - App.globalGet(total_active_stake_key)),
@>        App.globalPut(total_rewards_key, new_total_rewards.load()),
        # update unclaimed fees
@>        App.globalPut(total_unclaimed_fees_key, App.globalGet(total_unclaimed_fees_key) + mul_scale(
            new_total_rewards.load() - old_total_rewards.load(),
            App.globalGet(fee_key),
            ONE_4_DP
        )),
    )

The artificially low total_active_stake causes:

  • Inflated new_total_rewards calculation

  • Excessive fee collection since fees are taken as a percentage of rewards

  • Compounding effect as more burns occur over time

Impact Details

  • Loss of user funds through excessive fee collection(especially for the users that will keep the funds after several burn operations)

  • Rewards and fees are calculated on stake that is incorrectly classified as rewards

  • Impact compounds over time with each burn operation

Recommendation

The burn operation should reduce total_active_stake proportionally based only on the staked amount. i.e:

stake_reduction = mul_scale(
    burn_amount,
    App.globalGet(total_active_stake_key),
    get_x_algo_circulating_supply()
)

App.globalPut(total_active_stake_key, 
    App.globalGet(total_active_stake_key) - stake_reduction)

Proof of Concept

The PoC shows the tracking of how total_active_stake decreases more than it should, which causes the protocol to misclassify staked funds as rewards.

Another observation is that the helper functions of the PoC is merely copy/paste code from the original test suite. I've done this so I could separate the test in a new file but still preserve the state and use the same logic.

Create a new test file called incorrect-burning.test.ts and paste the following code into it:

import {
    ABIContract,
    Account,
    Algodv2,
    AtomicTransactionComposer,
    decodeAddress,
    decodeUint64,
    encodeUint64,
    generateAccount,
    getApplicationAddress,
    getMethodByName,
    IntDecoding,
    makeApplicationCreateTxn,
    makeApplicationUpdateTxn,
    makeBasicAccountTransactionSigner,
    modelsv2,
    OnApplicationComplete,
  } from "algosdk";
  import { mulScale, mulScaleRoundUp, ONE_16_DP, ONE_4_DP } from "folks-finance-js-sdk";
  import { sha256 } from "js-sha256";
  import { prepareOptIntoAssetTxn } from "./transactions/common";
  import {
    parseXAlgoConsensusV1GlobalState,
    prepareAddProposerForXAlgoConsensus,
    prepareBurnFromXAlgoConsensusV2,
    prepareClaimDelayedMintFromXAlgoConsensus,
    prepareClaimXAlgoConsensusV2Fee,
    prepareDelayedMintFromXAlgoConsensusV2,
    prepareImmediateMintFromXAlgoConsensusV2,
    prepareInitialiseXAlgoConsensusV1,
    prepareInitialiseXAlgoConsensusV2,
    preparePauseXAlgoConsensusMinting,
    prepareRegisterXAlgoConsensusOffline,
    prepareRegisterXAlgoConsensusOnline,
    prepareScheduleXAlgoConsensusSCUpdate,
    prepareUpdateXAlgoConsensusAdmin,
    prepareUpdateXAlgoConsensusV2Fee,
    prepareUpdateXAlgoConsensusPremium,
    prepareUpdateXAlgoConsensusMaxProposerBalance,
    prepareUpdateXAlgoConsensusSC,
    prepareSetXAlgoConsensusProposerAdmin,
    prepareSubscribeXAlgoConsensusProposerToXGov,
    prepareUnsubscribeXAlgoConsensusProposerFromXGov,
    prepareXAlgoConsensusDummyCall,
    parseXAlgoConsensusV2GlobalState,
    prepareCreateXAlgoConsensusV1,
    prepareMintFromXAlgoConsensusV1,
  } from "./transactions/xAlgoConsensus";
  import { getABIContract } from "./utils/abi";
  import { getAlgoBalance, getAssetBalance } from "./utils/account";
  import {
    compilePyTeal,
    compileTeal,
    enc,
    getAppGlobalState,
    getParsedValueFromState,
    parseUint64s
  } from "./utils/contracts";
  import { fundAccountWithAlgo } from "./utils/fund";
  import { privateAlgodClient, startPrivateNetwork, stopPrivateNetwork } from "./utils/privateNetwork";
  import { advanceBlockRounds, advancePrevBlockTimestamp } from "./utils/time";
  import { getParams, submitGroupTransaction, submitTransaction } from "./utils/transaction";
import fs from 'fs';
  
  jest.setTimeout(1000000);
  
  describe("Algo Consensus V2", () => {
    let algodClient: Algodv2;
    let prevBlockTimestamp: bigint;
    let user1: Account = generateAccount();
    let user2: Account = generateAccount();
    let proposer0: Account = generateAccount();
    let proposer1: Account = generateAccount();
    let admin: Account = generateAccount();
    let registerAdmin: Account = generateAccount();
    let xGovAdmin: Account = generateAccount();
    let proposerAdmin: Account = generateAccount();
    let xAlgoAppId: number, xAlgoId: number;
    let xAlgoConsensusABI: ABIContract;
  
    let xGovRegistryAppId: number;
    let xGovRegistryABI: ABIContract;
    let xGovFee: bigint;
  
    const timeDelay = BigInt(86400);
    const minProposerBalance = BigInt(5e6);
    const maxProposerBalance = BigInt(500e6);
    const premium = BigInt(0.001e16); // 0.1%
    const fee = BigInt(0.1e4); // 10%
  
    const nonce = Uint8Array.from([0, 0]);
    const resizeProposerBoxCost = BigInt(16000);
    const updateSCBoxCost = BigInt(32100);
    const delayMintBoxCost = BigInt(36100);

    beforeAll(async () => {
        console.log("Starting private network...");
        await startPrivateNetwork();
    
        const netConfig = Buffer.from(fs.readFileSync("net1/Primary/algod.net")).toString();
        const [host, port] = netConfig.split(":");
        console.log(`Using host: ${host}, port: ${port}`);
    
        try {
            const response = await fetch(`http://${host}:${port}/health`);
            if (!response.ok) {
                throw new Error(`Algod health check failed with status: ${response.status}`);
            }
            console.log("Algod is healthy.");
        } catch (error) {
            console.error("Failed to connect to Algod:", error);
            throw error;
        }
    
        algodClient = privateAlgodClient();
        algodClient.setIntEncoding(IntDecoding.MIXED);
    
        // initialise accounts with algo
        await fundAccountWithAlgo(algodClient, user1.addr, 1000e6, await getParams(algodClient));
        await fundAccountWithAlgo(algodClient, user2.addr, 1000e6, await getParams(algodClient));
        await fundAccountWithAlgo(algodClient, admin.addr, 1000e6, await getParams(algodClient));
        await fundAccountWithAlgo(algodClient, registerAdmin.addr, 1000e6, await getParams(algodClient));
        await fundAccountWithAlgo(algodClient, xGovAdmin.addr, 1000e6, await getParams(algodClient));
        await fundAccountWithAlgo(algodClient, proposerAdmin.addr, 1000e6, await getParams(algodClient));
    
        // advance time well past current time so we are dealing with deterministic time using offsets
        prevBlockTimestamp = await advancePrevBlockTimestamp(algodClient, 1000);
    
        // deploy xgov registry
        const approval = await compileTeal(compilePyTeal('contracts/testing/xgov_registry'));
        const clear = await compileTeal(compilePyTeal('contracts/common/clear_program', 10));
        const tx = makeApplicationCreateTxn(user1.addr, await getParams(algodClient), OnApplicationComplete.NoOpOC, approval, clear, 0, 0, 1, 0);
        const txId = await submitTransaction(algodClient, tx, user1.sk);
        const txInfo = await algodClient.pendingTransactionInformation(txId).do();
        xGovRegistryAppId = txInfo["application-index"];
        xGovRegistryABI = getABIContract('contracts/testing/xgov_registry');
        xGovFee = BigInt(getParsedValueFromState(await getAppGlobalState(algodClient, xGovRegistryAppId), "xgov_fee") || 0);
    });

    afterAll(() => {
        stopPrivateNetwork();
    });

    describe("Burn", () => {
        beforeEach(async () => {
          await initializeXAlgoConsensusV2();
          await updateAdmins();
          await addProposer();
          await setProposerAdmin();
          await registerOnline();
          await registerOffline();
          await setupImmediateMint();
        });
        test("When burning, the protocol misclassify staked funds as rewards ", async () => {
            // Initial setup - Send rewards to proposers to simulate earnings
            const rewards = BigInt(10e6); 
            await fundAccountWithAlgo(algodClient, proposer0.addr, rewards);
            await fundAccountWithAlgo(algodClient, proposer1.addr, rewards);
            
            const proposerAddrs = [proposer0.addr, proposer1.addr];
            
            // First mint
            const mintAmount = BigInt(200e6);
            const minReceived = BigInt(0);
            let txns = [
                prepareXAlgoConsensusDummyCall(xAlgoConsensusABI, xAlgoAppId, user1.addr, [], await getParams(algodClient)),
                ...prepareImmediateMintFromXAlgoConsensusV2(
                    xAlgoConsensusABI, 
                    xAlgoAppId,
                    xAlgoId,
                    user1.addr,
                    mintAmount,
                    minReceived,
                    proposerAddrs,
                    await getParams(algodClient)
                )
            ];
            await submitGroupTransaction(algodClient, txns, txns.map(() => user1.sk));
        
            // Get state after mint
            let stateBefore = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
            let { algoBalance: balanceBefore, xAlgoCirculatingSupply: supplyBefore } = await getXAlgoRate();
            
            console.log("\nAfter Initial Mint:");
            console.log("Total Active Stake:", stateBefore.totalActiveStake.toString());
            console.log("Total Rewards:", stateBefore.totalRewards.toString());
            console.log("ALGO Balance:", balanceBefore.toString());
            console.log("xALGO Supply:", supplyBefore.toString());
        
            // First burn - 25% of xALGO
            const burnAmount1 = supplyBefore / BigInt(4);
            txns = [
                prepareXAlgoConsensusDummyCall(xAlgoConsensusABI, xAlgoAppId, user1.addr, [], await getParams(algodClient)),
                ...prepareBurnFromXAlgoConsensusV2(
                    xAlgoConsensusABI,
                    xAlgoAppId,
                    xAlgoId,
                    user1.addr,
                    burnAmount1,
                    BigInt(0),
                    proposerAddrs,
                    await getParams(algodClient)
                )
            ];
            await submitGroupTransaction(algodClient, txns, txns.map(() => user1.sk));
        
            // Check state after first burn
            let stateAfterBurn1 = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
            let { algoBalance: balanceAfterBurn1 } = await getXAlgoRate();
            
            console.log("\nAfter First Burn (25%):");
            console.log("Total Active Stake:", stateAfterBurn1.totalActiveStake.toString());
            console.log("Total Rewards:", stateAfterBurn1.totalRewards.toString());
            console.log("ALGO Balance:", balanceAfterBurn1.toString());
        
            // Calculate expected stake reduction for first burn
            const expectedStakeReduction1 = (stateBefore.totalActiveStake * burnAmount1) / supplyBefore;
            const actualStakeReduction1 = stateBefore.totalActiveStake - stateAfterBurn1.totalActiveStake;
        
            console.log("\nFirst Burn Analysis:");
            console.log("Expected Stake Reduction:", expectedStakeReduction1.toString());
            console.log("Actual Stake Reduction:", actualStakeReduction1.toString());
            
            // Verify first burn reduced stake too much
            expect(actualStakeReduction1).toBeGreaterThan(expectedStakeReduction1);
            
            // Second burn to demonstrate compounding error
            const burnAmount2 = supplyBefore / BigInt(4);
            txns = [
                prepareXAlgoConsensusDummyCall(xAlgoConsensusABI, xAlgoAppId, user1.addr, [], await getParams(algodClient)),
                ...prepareBurnFromXAlgoConsensusV2(
                    xAlgoConsensusABI,
                    xAlgoAppId,
                    xAlgoId,
                    user1.addr,
                    burnAmount2,
                    BigInt(0),
                    proposerAddrs,
                    await getParams(algodClient)
                )
            ];
            await submitGroupTransaction(algodClient, txns, txns.map(() => user1.sk));
        
            // Final state check
            const finalState = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
            
            // Calculate total expected stake reduction
            const totalExpectedReduction = (expectedStakeReduction1 * BigInt(2));
            const totalActualReduction = stateBefore.totalActiveStake - finalState.totalActiveStake;
        
            console.log("\nFinal Analysis:"); 
            console.log("Total Expected Reduction:", totalExpectedReduction.toString());
            console.log("Total Actual Reduction:", totalActualReduction.toString());
            console.log("Final Active Stake:", finalState.totalActiveStake.toString());
            console.log("Final Rewards:", finalState.totalRewards.toString());
        
            // Verify compounding error made total reduction too large
            expect(totalActualReduction).toBeGreaterThan(totalExpectedReduction);
        });
    });

    // HELPER FUNCTIONS
    async function getXAlgoRate() {
        const atc = new AtomicTransactionComposer();
        atc.addMethodCall({
          sender: user1.addr,
          signer: makeBasicAccountTransactionSigner(user1),
          appID: xAlgoAppId,
          method: getMethodByName(xAlgoConsensusABI.methods, "get_xalgo_rate"),
          methodArgs: [],
          suggestedParams: await getParams(algodClient),
        });
        const simReq = new modelsv2.SimulateRequest({
          txnGroups: [],
          allowUnnamedResources: true,
        })
        const { methodResults }  = await atc.simulate(algodClient, simReq);
        const { returnValue } = methodResults[0];
        const [algoBalance, xAlgoCirculatingSupply, balances]: [bigint, bigint, Uint8Array] = returnValue as any;
        const proposersBalances = parseUint64s(Buffer.from(balances).toString("base64"));
        return { algoBalance, xAlgoCirculatingSupply, proposersBalances } ;
      }
  
      // async function to initialize the application.
      async function initializeXAlgoConsensusV2() {
          // deploy algo consensus v1
        const { tx: createTx, abi } = await prepareCreateXAlgoConsensusV1(admin.addr, admin.addr, registerAdmin.addr, minProposerBalance, maxProposerBalance, premium, fee, await getParams(algodClient));
        xAlgoConsensusABI = abi;
        let txId = await submitTransaction(algodClient, createTx, admin.sk);
        let txInfo = await algodClient.pendingTransactionInformation(txId).do();
        xAlgoAppId = txInfo["application-index"];
  
        // fund minimum balance
        await fundAccountWithAlgo(algodClient, proposer0.addr, BigInt(0.1e6), await getParams(algodClient));
        await fundAccountWithAlgo(algodClient, getApplicationAddress(xAlgoAppId), 0.6034e6);
  
        // initialise algo consensus v1
        const initTxns = prepareInitialiseXAlgoConsensusV1(xAlgoConsensusABI, xAlgoAppId, admin.addr, proposer0.addr, await getParams(algodClient));
        [, txId] = await submitGroupTransaction(algodClient, initTxns, [proposer0.sk, admin.sk]);
        txInfo = await algodClient.pendingTransactionInformation(txId).do();
        xAlgoId = txInfo['inner-txns'][0]['asset-index'];
  
        // verify xAlgo was created
        const assetInfo = await algodClient.getAssetByID(xAlgoId).do();
        expect(assetInfo.params.creator).toEqual(getApplicationAddress(xAlgoAppId));
        expect(assetInfo.params.reserve).toEqual(getApplicationAddress(xAlgoAppId));
        expect(assetInfo.params.total).toEqual(BigInt(10e15));
        expect(assetInfo.params.decimals).toEqual(6);
        expect(assetInfo.params.name).toEqual('Governance xAlgo');
        expect(assetInfo.params['unit-name']).toEqual('xALGO');
  
        // opt into xALGO
        let optInTx = prepareOptIntoAssetTxn(admin.addr, xAlgoId, await getParams(algodClient));
        await submitTransaction(algodClient, optInTx, admin.sk);
        optInTx = prepareOptIntoAssetTxn(user1.addr, xAlgoId, await getParams(algodClient));
        await submitTransaction(algodClient, optInTx, user1.sk);
        optInTx = prepareOptIntoAssetTxn(user2.addr, xAlgoId, await getParams(algodClient));
        await submitTransaction(algodClient, optInTx, user2.sk);
  
        // mint to get pool started
        const mintAmount = BigInt(100e6);
        const mintTxns = prepareMintFromXAlgoConsensusV1(xAlgoConsensusABI, xAlgoAppId, xAlgoId, user2.addr, mintAmount, proposer0.addr, await getParams(algodClient));
        await submitGroupTransaction(algodClient, mintTxns, mintTxns.map(() => user2.sk));
  
        // verify global state
        const state = await parseXAlgoConsensusV1GlobalState(algodClient, xAlgoAppId);
        expect(state.initialised).toEqual(true);
        expect(state.admin).toEqual(admin.addr);
        expect(state.registerAdmin).toEqual(registerAdmin.addr);
        expect(state.xAlgoId).toEqual(xAlgoId);
        expect(state.numProposers).toEqual(BigInt(1));
        expect(state.minProposerBalance).toEqual(minProposerBalance);
        expect(state.maxProposerBalance).toEqual(maxProposerBalance);
        expect(state.fee).toEqual(fee);
        expect(state.premium).toEqual(premium);
        expect(state.totalPendingStake).toEqual(BigInt(0));
        expect(state.totalActiveStake).toEqual(mintAmount);
        expect(state.totalRewards).toEqual(BigInt(0));
        expect(state.totalUnclaimedFees).toEqual(BigInt(0));
        expect(state.canImmediateMint).toEqual(true);
        expect(state.canDelayMint).toEqual(false);
  
        // verify proposers box
        const proposersBox = await algodClient.getApplicationBoxByName(xAlgoAppId, enc.encode("pr")).do();
        const proposers = new Uint8Array(960);
        proposers.set(decodeAddress(proposer0.addr).publicKey, 0);
        expect(proposersBox.value).toEqual(proposers);
  
        // verify added proposer box
        const boxName = Uint8Array.from([...enc.encode("ap"), ...decodeAddress(proposer0.addr).publicKey]);
        const addedProposerBox = await algodClient.getApplicationBoxByName(xAlgoAppId, boxName).do();
        expect(addedProposerBox.value).toEqual(new Uint8Array(0));
  
        // verify balances
        const user2XAlgoBalance = await getAssetBalance(algodClient, user2.addr, xAlgoId);
        expect(user2XAlgoBalance).toEqual(mintAmount);
  
        // update to algo consensus v2
        const approval = await compileTeal(compilePyTeal('contracts/xalgo/consensus_v2'));
        const clear = await compileTeal(compilePyTeal('contracts/common/clear_program', 10));
        const updateTx = makeApplicationUpdateTxn(admin.addr, await getParams(algodClient), xAlgoAppId, approval, clear);
        await submitTransaction(algodClient, updateTx, admin.sk);
        xAlgoConsensusABI = getABIContract('contracts/xalgo/consensus_v2');
  
  
        // initialise
        const oldState = await parseXAlgoConsensusV1GlobalState(algodClient, xAlgoAppId);
  
        // initialise
        const tx = prepareInitialiseXAlgoConsensusV2(xAlgoConsensusABI, xAlgoAppId, admin.addr, await getParams(algodClient));
        await submitTransaction(algodClient, tx, admin.sk);
  
        // verify global state
        const unformattedState = await getAppGlobalState(algodClient, xAlgoAppId);
        expect(getParsedValueFromState(unformattedState, "initialised")).toBeUndefined();
        expect(getParsedValueFromState(unformattedState, "min_proposer_balance")).toBeUndefined();
  
        const newState = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
        expect(newState.initialised).toEqual(true);
        expect(newState.admin).toEqual(oldState.admin);
        expect(newState.xGovAdmin).toEqual(oldState.admin);
        expect(newState.registerAdmin).toEqual(oldState.registerAdmin);
        expect(newState.xAlgoId).toEqual(oldState.xAlgoId);
        expect(newState.numProposers).toEqual(oldState.numProposers);
        expect(newState.maxProposerBalance).toEqual(oldState.maxProposerBalance);
        expect(newState.fee).toEqual(oldState.fee);
        expect(newState.premium).toEqual(oldState.premium);
        expect(newState.totalPendingStake).toEqual(oldState.totalPendingStake);
        expect(newState.totalActiveStake).toEqual(oldState.totalActiveStake);
        expect(newState.totalRewards).toEqual(oldState.totalRewards);
        expect(newState.totalUnclaimedFees).toEqual(oldState.totalUnclaimedFees);
        expect(newState.canImmediateMint).toEqual(oldState.canImmediateMint);
        expect(newState.canDelayMint).toEqual(oldState.canDelayMint);
      }
  
      async function setupImmediateMint() { 
        const { canImmediateMint, canDelayMint } = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
  
        // update pause minting
        let tx = preparePauseXAlgoConsensusMinting(xAlgoConsensusABI, xAlgoAppId, admin.addr, "can_immediate_mint", canImmediateMint, await getParams(algodClient));
        await submitTransaction(algodClient, tx, admin.sk);
        tx = preparePauseXAlgoConsensusMinting(xAlgoConsensusABI, xAlgoAppId, admin.addr, "can_delay_mint", canDelayMint, await getParams(algodClient));
        await submitTransaction(algodClient, tx, admin.sk);
        let state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
        expect(state.canImmediateMint).toEqual(!canImmediateMint);
        expect(state.canDelayMint).toEqual(!canDelayMint);
  
        // restore pause minting
        tx = preparePauseXAlgoConsensusMinting(xAlgoConsensusABI, xAlgoAppId, admin.addr, "can_immediate_mint", !canImmediateMint, await getParams(algodClient));
        await submitTransaction(algodClient, tx, admin.sk);
        tx = preparePauseXAlgoConsensusMinting(xAlgoConsensusABI, xAlgoAppId, admin.addr, "can_delay_mint", !canDelayMint, await getParams(algodClient));
        await submitTransaction(algodClient, tx, admin.sk);
        state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
        expect(state.canImmediateMint).toEqual(canImmediateMint);
        expect(state.canDelayMint).toEqual(canDelayMint);
      }
  
      async function addProposer() { 
          const minBalance = BigInt(16100);
          await fundAccountWithAlgo(algodClient, getApplicationAddress(xAlgoAppId), minBalance, await getParams(algodClient));
          await fundAccountWithAlgo(algodClient, proposer1.addr, BigInt(0.1e6), await getParams(algodClient));
    
          // balances before
          const proposerAlgoBalanceB = await getAlgoBalance(algodClient, proposer0.addr);
          const appAlgoBalanceB = await getAlgoBalance(algodClient, getApplicationAddress(xAlgoAppId));
          let state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
          const { totalActiveStake: oldTotalActiveStake } = state;
    
          // register
          const txns = prepareAddProposerForXAlgoConsensus(xAlgoConsensusABI, xAlgoAppId, registerAdmin.addr, proposer1.addr, await getParams(algodClient));
          const [, txId] = await submitGroupTransaction(algodClient, txns, [proposer1.sk, registerAdmin.sk]);
          const txInfo = await algodClient.pendingTransactionInformation(txId).do();
          state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
          expect(state.totalActiveStake).toEqual(oldTotalActiveStake);
    
          // balances after
          const { proposersBalances } = await getXAlgoRate();
          const proposerAlgoBalanceA = await getAlgoBalance(algodClient, proposer0.addr);
          const appAlgoBalanceA = await getAlgoBalance(algodClient, getApplicationAddress(xAlgoAppId));
          expect(proposersBalances.length).toEqual(2);
          expect(proposersBalances[1]).toEqual(BigInt(0.1e6));
          expect(proposerAlgoBalanceA).toEqual(proposerAlgoBalanceB);
          expect(appAlgoBalanceA).toEqual(appAlgoBalanceB);
          expect(txInfo['inner-txns']).toBeUndefined();
    
          // verify proposers box
          const proposersBox = await algodClient.getApplicationBoxByName(xAlgoAppId, enc.encode("pr")).do();
          const proposers = new Uint8Array(960);
          proposers.set(decodeAddress(proposer0.addr).publicKey, 0);
          proposers.set(decodeAddress(proposer1.addr).publicKey, 32);
          expect(proposersBox.value).toEqual(proposers);
    
          // verify added proposer box
          const boxName = Uint8Array.from([...enc.encode("ap"), ...decodeAddress(proposer1.addr).publicKey]);
          const addedProposerBox = await algodClient.getApplicationBoxByName(xAlgoAppId, boxName).do();
          expect(addedProposerBox.value).toEqual(new Uint8Array(0));
      }

    async function updateAdmins() { 
      // admin updating admin
      let tx = prepareUpdateXAlgoConsensusAdmin(xAlgoConsensusABI, xAlgoAppId, "admin", admin.addr, user1.addr, await getParams(algodClient));
      await submitTransaction(algodClient, tx, admin.sk);
      let state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
      expect(state.admin).toEqual(user1.addr);

      // restore old admin
      tx = prepareUpdateXAlgoConsensusAdmin(xAlgoConsensusABI, xAlgoAppId, "admin", user1.addr, admin.addr, await getParams(algodClient));
      await submitTransaction(algodClient, tx, user1.sk);
      state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
      expect(state.admin).toEqual(admin.addr);

      // admin updating register admin
      tx = prepareUpdateXAlgoConsensusAdmin(xAlgoConsensusABI, xAlgoAppId, "register_admin", admin.addr, user1.addr, await getParams(algodClient));
      await submitTransaction(algodClient, tx, admin.sk);
      state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
      expect(state.registerAdmin).toEqual(user1.addr);

      // register admin updating register admin
      tx = prepareUpdateXAlgoConsensusAdmin(xAlgoConsensusABI, xAlgoAppId, "register_admin", user1.addr, registerAdmin.addr, await getParams(algodClient));
      await submitTransaction(algodClient, tx, user1.sk);
      state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
      expect(state.registerAdmin).toEqual(registerAdmin.addr);

      // admin updating xgov admin
      tx = prepareUpdateXAlgoConsensusAdmin(xAlgoConsensusABI, xAlgoAppId, "xgov_admin", admin.addr, user1.addr, await getParams(algodClient));
      await submitTransaction(algodClient, tx, admin.sk);
      state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
      expect(state.xGovAdmin).toEqual(user1.addr);

      // xgov admin updating xgov admin
      tx = prepareUpdateXAlgoConsensusAdmin(xAlgoConsensusABI, xAlgoAppId, "xgov_admin", user1.addr, xGovAdmin.addr, await getParams(algodClient));
      await submitTransaction(algodClient, tx, user1.sk);
      state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
      expect(state.xGovAdmin).toEqual(xGovAdmin.addr);
    }

    async function updatePremium() {
       // update premium
       const tempPremium = BigInt(0.0025e16);
       let tx = prepareUpdateXAlgoConsensusPremium(xAlgoConsensusABI, xAlgoAppId, admin.addr, tempPremium, await getParams(algodClient));
       await submitTransaction(algodClient, tx, admin.sk);
       let state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
       expect(state.premium).toEqual(tempPremium);
 
       // restore old premium
       tx = prepareUpdateXAlgoConsensusPremium(xAlgoConsensusABI, xAlgoAppId, admin.addr, premium, await getParams(algodClient));
       await submitTransaction(algodClient, tx, admin.sk);
       state = await parseXAlgoConsensusV2GlobalState(algodClient, xAlgoAppId);
       expect(state.premium).toEqual(premium);
    }

    async function setProposerAdmin() {
        const boxName = Uint8Array.from([...enc.encode("ap"), ...decodeAddress(proposer0.addr).publicKey]);
        let addedProposerBox = await algodClient.getApplicationBoxByName(xAlgoAppId, boxName).do();
        expect(addedProposerBox.value).toEqual(new Uint8Array(0));

        // fund box
        await fundAccountWithAlgo(algodClient, getApplicationAddress(xAlgoAppId), resizeProposerBoxCost, await getParams(algodClient));

        // immediate if no existing proposer admin
        let tx = prepareSetXAlgoConsensusProposerAdmin(xAlgoConsensusABI, xAlgoAppId, registerAdmin.addr, 0, proposer0.addr, user1.addr, await getParams(algodClient));
        await submitTransaction(algodClient, tx, registerAdmin.sk)
        addedProposerBox = await algodClient.getApplicationBoxByName(xAlgoAppId, boxName).do();
        expect(addedProposerBox.value).toEqual(Uint8Array.from([...encodeUint64(prevBlockTimestamp), ...decodeAddress(user1.addr).publicKey]));

        // delay if existing proposer admin
        tx = prepareSetXAlgoConsensusProposerAdmin(xAlgoConsensusABI, xAlgoAppId, registerAdmin.addr, 0, proposer0.addr, proposerAdmin.addr, await getParams(algodClient));
        await submitTransaction(algodClient, tx, registerAdmin.sk)
        addedProposerBox = await algodClient.getApplicationBoxByName(xAlgoAppId, boxName).do();
        expect(addedProposerBox.value).toEqual(Uint8Array.from([...encodeUint64(prevBlockTimestamp + timeDelay), ...decodeAddress(proposerAdmin.addr).publicKey]));

        // proceed to timestamp after timeDelay
        const box = await algodClient.getApplicationBoxByName(xAlgoAppId, boxName).do();
        const ts = decodeUint64(box.value.subarray(0, 8), "bigint");
        const offset = Number(ts - prevBlockTimestamp) + 1;
        prevBlockTimestamp = await advancePrevBlockTimestamp(algodClient, offset);
    }

    async function registerOnline() { 
        const registerFeeAmount = BigInt(2e6);
        const voteKey = Buffer.from("G/lqTV6MKspW6J8wH2d8ZliZ5XZVZsruqSBJMwLwlmo=", "base64");
        const selKey = Buffer.from("LrpLhvzr+QpN/bivh6IPpOaKGbGzTTB5lJtVfixmmgk=", "base64");
        const stateProofKey = Buffer.from("Nn0fiJDZH2wyLqxNzrOC3WPF8Vz3AH8JU1IGI2H2xdcnRiqw7YuWkohuKHpC1EJMAe6ZVbUS/S2rPeCRAolfRQ==", "base64");
        const voteFirstRound = 1;
        const voteLastRound = 5000;
        const voteKeyDilution = 1500;

        const txns = prepareRegisterXAlgoConsensusOnline(xAlgoConsensusABI, xAlgoAppId, proposerAdmin.addr, registerFeeAmount, 0, proposer0.addr, voteKey, selKey, stateProofKey, voteFirstRound, voteLastRound, voteKeyDilution, await getParams(algodClient));
        const [, txId] = await submitGroupTransaction(algodClient, txns, txns.map(() => proposerAdmin.sk));
        const txInfo = await algodClient.pendingTransactionInformation(txId).do();

        // check key registration
        const innerRegisterOnlineTx = txInfo['inner-txns'][0]['txn']['txn'];
        expect(innerRegisterOnlineTx.type).toEqual('keyreg');
        expect(innerRegisterOnlineTx.snd).toEqual(Uint8Array.from(decodeAddress(proposer0.addr).publicKey));
        expect(innerRegisterOnlineTx.votekey).toEqual(Uint8Array.from(voteKey));
        expect(innerRegisterOnlineTx.selkey).toEqual(Uint8Array.from(selKey));
        expect(innerRegisterOnlineTx.sprfkey).toEqual(Uint8Array.from(stateProofKey));
        expect(innerRegisterOnlineTx.votefst).toEqual(voteFirstRound);
        expect(innerRegisterOnlineTx.votelst).toEqual(voteLastRound);
        expect(innerRegisterOnlineTx.votekd).toEqual(voteKeyDilution);
        expect(innerRegisterOnlineTx.fee).toEqual(Number(registerFeeAmount));
    }

    async function registerOffline() { 
        for (const sender of [registerAdmin, proposerAdmin]) {
            const tx = prepareRegisterXAlgoConsensusOffline(xAlgoConsensusABI, xAlgoAppId, sender.addr, 0, proposer0.addr, await getParams(algodClient));
            const txId = await submitTransaction(algodClient, tx, sender.sk);
            const txInfo = await algodClient.pendingTransactionInformation(txId).do();
    
            // check key registration
            const innerRegisterOnlineTx = txInfo['inner-txns'][0]['txn']['txn'];
            expect(innerRegisterOnlineTx.type).toEqual('keyreg');
            expect(innerRegisterOnlineTx.snd).toEqual(Uint8Array.from(decodeAddress(proposer0.addr).publicKey));
            expect(innerRegisterOnlineTx.votekey).toBeUndefined();
            expect(innerRegisterOnlineTx.selkey).toBeUndefined();
            expect(innerRegisterOnlineTx.sprfkey).toBeUndefined();
            expect(innerRegisterOnlineTx.votefst).toBeUndefined();
            expect(innerRegisterOnlineTx.votelst).toBeUndefined();
            expect(innerRegisterOnlineTx.votekd).toBeUndefined();
            expect(innerRegisterOnlineTx.fee).toBeUndefined();
          }
    }
  });

then run: PYTHONPATH="./contracts" npx jest test/incorrect-burning.test.ts --runInBand

Output:

Final Analysis:
Total Expected Reduction: 149999998
Total Actual Reduction: 158999998 
Final Active Stake: 141000002
Final Rewards: 20000000

PASS test/incorrect-burning.test.ts (11.539 s)
Algo Consensus V2 Burn 
✓ When burning, the protocol misclassify staked funds as rewards (4263 ms)
Previous#37660 [SC-High] incorrect tracking of `TOTAL_ACTIVE_STAKE` leads to permanent freezing of fundsNext#37768 [SC-Insight] Missing Event Emission when proposer are added prevents safe retrieval of index for subsequent operations