GivingThanks

Summary

The CharityRegistry contract lacks functionality to deregister or unverify charities, making it impossible to remove malicious or compromised charities from the system. Once registered, a charity remains permanently eligible to receive donations.

Vulnerability Details

The vulnerability exists in the CharityRegistry.sol contract.

Key issues:

1. No function to remove a charity's registration

2. No function to revoke a charity's verification status

3. No way to blacklist compromised addresses

4. Permanent verification status even if charity is compromised

Several scenarios where this becomes critical:

• A charity's private keys are compromised

• A charity is found to be fraudulent after verification

• A charity's smart contract is exploited

• Legal requirements mandate the removal of a charity

• A charity closes operations but their address remains verified

Impact

• Severity: High

• Likelihood: Medium (requires charity compromise or admin verification mistake)

Effects:

1. Compromised charities remain permanently in the system

2. No way to stop donations to malicious actors

3. Reduced trust in platform security

4. Potential loss of donor funds to compromised charities

5. Reputational damage to platform if compromised charity misuses funds

6. No compliance mechanism if legal removal is required

Tools Used

Manual code review

Recommendations

1. Add deregistration and unverification functionality:

Additionally, consider:

1. Adding a blacklist mechanism for known malicious addresses

2. Implementing a time-lock for charity verification changes

3. Adding multi-signature requirements for verification actions

4. Creating an emergency pause function for specific charities

5. Implementing a charity status history log

Example of blacklist implementation: