Conducting regular security audits

Oct 13, 2025 by talynt.org 42 views

Precise Bubblegum Boa - Anyone can delay reward distribution by calling notifyRewardAmount with minimal Deposits

In the world of decentralized finance (DeFi), smart contracts play a crucial role in facilitating various financial transactions. However, with the increasing complexity of these contracts, vulnerabilities can arise, allowing malicious actors to exploit them. In this article, we will delve into a specific vulnerability found in the SymmStaking contract, which enables an attacker to delay reward distribution by calling the notifyRewardAmount() function with minimal deposits.

An attacker can continuously delay the distribution of staking rewards by calling notifyRewardAmount() with small amounts of tokens. Since each call extends the periodFinish by duration, this prevents timely reward distribution to stakers.

The function notifyRewardAmount() updates the periodFinish to block.timestamp + duration every time it is called, regardless of the deposited amount. This allows any user to extend the reward period indefinitely by calling the function with small token amounts.

https://github.com/sherlock-audit/2025-03-symm-io-stacking/blob/d7cf7fc96af1c25b53a7b500a98b411cd018c0d3/token/contracts/staking/SymmStaking.sol#L275C2-L292C3

https://github.com/sherlock-audit/2025-03-symm-io-stacking/blob/d7cf7fc96af1c25b53a7b500a98b411cd018c0d3/token/contracts/staking/SymmStaking.sol#L366C2-L379C3

The attacker calls notifyRewardAmount() with a very small amount of a reward token. The function updates the reward period finish time (periodFinish = block.timestamp + duration), delaying the reward distribution. The attacker repeats the process, ensuring that periodFinish never arrives, effectively preventing users from claiming their rewards.

Reward distribution for stakers will be delayed. This can have significant consequences, including:

Loss of interest: Stakers may miss out on interest earned on their rewards.
Reduced liquidity: Delayed reward distribution can lead to reduced liquidity in the market.
Decreased user trust: Repeated delays in reward distribution can erode user trust in the platform.

To prevent this vulnerability, access control should be added to the notifyRewardAmount() function. This can be achieved by implementing a permission system, where only authorized users can call the function. Additionally, the function can be modified to only update the periodFinish when a significant amount of tokens is deposited.

The Precise Bubblegum Boa vulnerability highlights the importance of thorough security audits and testing in the development of smart contracts. By identifying and addressing vulnerabilities early on, developers can ensure the security and integrity of their contracts, protecting users from potential losses. As the DeFi space continues to evolve, it is essential to prioritize security and transparency in the development of financial applications.

Regular security audits: Conduct regular security audits to identify and address potential vulnerabilities.
Access control: Implement access control mechanisms to restrict who can call critical functions.
Testing: Thoroughly test contracts to ensure they function as intended.
Transparency: Prioritize transparency in the development and deployment of financial applications.

By following these recommendations, developers can create secure and reliable financial applications that protect users from potential losses.
Precise Bubblegum Boa - Anyone can delay reward distribution by calling notifyRewardAmount with minimal Deposits

Q: What is the Precise Bubblegum Boa vulnerability? A: The Precise Bubblegum Boa vulnerability is a security issue found in the SymmStaking contract, which allows an attacker to delay reward distribution by calling the notifyRewardAmount() function with minimal deposits.

Q: How does the attacker exploit the vulnerability? A: The attacker calls notifyRewardAmount() with a very small amount of a reward token, which updates the reward period finish time (periodFinish = block.timestamp + duration), delaying the reward distribution. The attacker repeats the process, ensuring that periodFinish never arrives, effectively preventing users from claiming their rewards.

Q: What are the consequences of the Precise Bubblegum Boa vulnerability? A: The consequences of the Precise Bubblegum Boa vulnerability include:

Loss of interest: Stakers may miss out on interest earned on their rewards.
Reduced liquidity: Delayed reward distribution can lead to reduced liquidity in the market.
Decreased user trust: Repeated delays in reward distribution can erode user trust in the platform.

Q: How can the Precise Bubblegum Boa vulnerability be mitigated? A: The Precise Bubblegum Boa vulnerability can be mitigated by:

Adding access control: Implementing a permission system to restrict who can call the notifyRewardAmount() function.
Modifying the function: Updating the function to only update the periodFinish when a significant amount of tokens is deposited.

Q: What is the importance of security audits in the development of smart contracts? A: Security audits are crucial in the development of smart contracts as they help identify and address potential vulnerabilities. Regular security audits can prevent security issues like the Precise Bubblegum Boa vulnerability from occurring.

Q: How can developers ensure the security and integrity of their smart contracts? A: Developers can ensure the security and integrity of their smart contracts by:

Conducting regular security audits: Identifying and addressing potential vulnerabilities.
Implementing access control: Restricting who can call critical functions.
Thoroughly testing: Ensuring contracts function as intended.
Prioritizing transparency: Being open and transparent in the development and deployment of financial applications.

Q: What is the impact of the Precise Bubblegum Boa vulnerability on the DeFi space? A: The Precise Bubblegum Boa vulnerability highlights the importance of security and transparency in the development of financial applications. It emphasizes the need for regular security audits, access control, and thorough testing to prevent security issues from occurring.

Q: How can users protect themselves from the Precise Bubblegum Boa vulnerability? A: Users can protect themselves from the Precise Bubblegum Boa vulnerability by:

Monitoring their rewards: Keeping track of their rewards and reporting any delays to the platform.
Verifying contract security: Ensuring the contract has undergone regular security audits and has implemented access control.
Choosing reputable platforms: Selecting platforms with a strong reputation for security and transparency.

By understanding the Precise Bubblegum Boa vulnerability and its consequences, users and developers can take steps to prevent security issues from occurring and ensure the integrity of financial applications.