RustFund
First Flight #36
Beginner FriendlyRust
100 EXP
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Submission Details
Severity: medium
Valid

Stale Funding Total Maintained After Refunds

0xluckyluke

Summary

The contract deducts lamports during refunds but doesn't reduce the amount_raised counter, creating a discrepancy between actual funds and displayed totals.

Vulnerability Details

The fund.amount_raised field acts as a deposit counter but never decreases, while real funds are reduced via lamport transfers.

https://github.com/CodeHawks-Contests/2025-03-rustfund/blob/b5dd7b0ec01471667ae3a02520701aae405ac857/programs/rustfund/src/lib.rs#L66-L88

pub fn refund(ctx: Context<FundRefund>) -> Result<()> {
​
let amount = ctx.accounts.contribution.amount;
if ctx.accounts.fund.deadline != 0 && ctx.accounts.fund.deadline > Clock::get().unwrap().unix_timestamp.try_into().unwrap() {
return Err(ErrorCode::DeadlineNotReached.into());
}
​
**ctx.accounts.fund.to_account_info().try_borrow_mut_lamports()? =
ctx.accounts.fund.to_account_info().lamports()
.checked_sub(amount)
.ok_or(ProgramError::InsufficientFunds)?;
**ctx.accounts.contributor.to_account_info().try_borrow_mut_lamports()? =
ctx.accounts.contributor.to_account_info().lamports()
.checked_add(amount)
.ok_or(ErrorCode::CalculationOverflow)?;
​
​
// Reset contribution amount after refund
ctx.accounts.contribution.amount = 0;
// MISSING: fund.amount_raised -= amount;
Ok(())
}

Impact

  • Withdrawal Failures: Creators may attempt withdrawals exceeding actual balances.

  • False Progress: Funding goals appear closer to completion than reality.

  • Trust Erosion: Users see inflated totals that don't match blockchain reality.

Tools Used

Recommendations

Add to refund() after lamport transfer

let fund = &mut ctx.accounts.fund;
fund.amount_raised = fund.amount_raised
.checked_sub(amount)
.ok_or(ErrorCode::CalculationOverflow)?;

Add validation in withdraw()

Updates

Appeal created

bube Lead Judge 7 months ago
Submission Judgement Published
Validated
Assigned finding tags:

`amount_raised` not updated in `refund` function

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