March 2026 Security Update

This page outlines the technical shifts from Legacy to Default security modes.

Following our successful month-long Honeypot challenge and expert reviews from HackenProof researchers, we have upgraded our wallet derivation architecture to provide higher resistance against specialized hardware (ASICs/GPUs) attacks. We maintain a "Legacy" mode to ensure backward compatibility for all wallets created before March 2026.

What we upgraded?

Scrypt Parameters

Scrypt Parameters	Legacy (Pre-March 2026)	Default (Current)
CPU/Memory Cost Parameter (N)	2^15	2^17
Parallelization Parameter (p)	5	1
Block Size Parameter (r)	8	8
keyLen	64	64

Salt Generation

• Legacy

const salt = `${passphrase.slice(-4)}${pin}`;
saltBuffer = Buffer.from(legacySalt);

• Default

const KDF_DOMAIN_SEPARATOR = "mybucks.online-core.generateHash.v2";
const encoded = abi.encode(
    ["string", "string", "string"],
    [KDF_DOMAIN_SEPARATOR, passphrase, pin],
);
const saltHash = ethers.keccak256(encoded);
saltBuffer = Buffer.from(saltHash.slice(2), "hex");

Why we upgraded?

• Hardened KDF Parameters: Following OWASP recommendations, we recognize that memory-hardness (N) is a more critical defense against modern hardware attacks than parallelization (p). By increasing the cost factor N from 2^15 to 2^17 and reducing p from 5 to 1, we have increased the memory requirements fourfold—from 32MB to 128MB. This significantly raises the barrier for attackers while maintaining a similar hashing time on the user's browser.

• Entropy Preservation in Salt Derivation: Our legacy salt generation inadvertently discarded significant entropy by only utilizing the final 4 characters of the passphrase. This created a potential vulnerability where different passphrases with common endings could generate identical salts. The new mechanism now incorporates the full passphrase into the salt derivation, ensuring that every unique credential produces a unique, high-entropy salt.

• Structured Encoding via abi.encode: To prevent salt-collision vulnerabilities, we replaced simple string concatenation with abi.encode. This ensures that the boundary between the Passphrase and PIN is cryptographically preserved. By using fixed-length offsets and length-prefixing for each input, we eliminate the risk of "Canonicalization Attacks," where two different credential pairs could accidentally produce the same concatenated salt.

• Domain Separation: To prevent cross-protocol attacks and the unauthorized reuse of hash results, we have introduced a Domain Separator into the salt generation process. This ensures that the keys derived for mybucks.online are cryptographically isolated and cannot be used to compromise or spoof other services.

User Action & Compatibility

For backward compatibility, we have added a new checkbox: 'This wallet was created before March 2026.'

If you are creating a new wallet after March 9, 2026, you can ignore this checkbox. If you need to access a wallet created before the update, please ensure the box is checked.

Deprecation of Legacy Mode

To maintain a streamlined and secure protocol, the "Legacy" checkbox is part of a temporary migration phase. We will support the Legacy derivation path for a sufficient period to allow all users to move their funds to the updated architecture.

After this migration window closes, the checkbox will be removed from the primary interface, and the Default mode will become the sole standard for mybucks.online.