GivingThanks

Summary

Anyone can modify the registry, leading to a shift in power, which could allow attackers to freely register charitable organizations.

Vulnerability Details

The source of the vulnerability code:
https://github.com/Cyfrin/2024-11-giving-thanks/blob/304812abfc16df934249ecd4cd8dea38568a625d/src/GivingThanks.sol#L56-L58

Detailed vulnerability code.

This function is public, meaning anyone can modify the registry. In other words, an attacker could register themselves as the registry and then provide the address of a charitable organization to register it. Only the admin is supposed to confirm the registration, but since the attacker has now become the admin, this creates a vulnerability that could be exploited for uncontrollable attacks.

Impact

An attacker can call the updateRegistry public function, passing their own address as a parameter to change the registry. Then, by calling the donate function again, the attacker could either pass their own address or another address, allowing them to illegally receive donated tokens and engage in malicious fundraising.

Tools Used

Manual review.

Recommendations

Add a require condition in theupdateRegistryfunction to restrict who can modify the registry.