Solana-Canton: Bridge Assessment (RUST) Audit | Memora

Summary

100% of all REPORTED Findings have been addressed

About this report

Assessment Type

Assurance Assessment

Date of Engagement

August 28th, 2026 - September 3rd, 2026

Source Code

memora-halborn

memora-halborn-e9f2daa5a3d9ddc92377a863ab69bc26d064124d.zip

Assessed Commit ID

https://github.com/rwishnow-memora/memora-halborn/tree/e9f2daa5a3d9ddc92377a863ab69bc26d064124d

Severity Breakdown

0Acknowledged
0Risk Accepted
7Solved
7All Findings

Critical0
High0
Medium0
Low4
- 4Solved
Informational3
- 3Solved

Introduction#

The Memora team engaged Halborn to conduct a security assessment of their Canton/Solana Bridge program beginning on August 28th, 2026, and ending on September 3rd, 2026. The security assessment was scoped to the Solana Programs provided in memora-halborn GitHub repository. Commit hashes and further details can be found in the Scope section of this report.

The program is the Solana-side vault of a Canton-Solana lock-and-mint bridge. It holds user funds in a PDA-owned vault, locks them on Deposit so Canton can mint a matching Holding, and releases them only under an attestor quorum when Canton signals a redemption or refund, with on-chain nonces preventing replay and a kill switch halting the bridge.

Assessment Summary#

Halborn was provided 5 days for the engagement and assigned one full-time security engineer to review the security of the Solana Programs in scope. The engineer is a blockchain and smart contract security expert with advanced smart contract hacking skills, and deep knowledge of multiple blockchain protocols.

The purpose of the assessment is to:

Identify potential security issues within the Solana Programs.
Ensure that smart contract functionality operates as intended.

In summary, Halborn identified some improvements to reduce the likelihood and impact of risks, which were addressed by the Memora team. The main ones were the following:

Require a stronger minimum attestor threshold.
Validate the pause authority and ensure it can provide its signature and manage the bridge.
Validate the bridge mint to be the expected mint.
Consider implementing instructions to rotate attestors and update the threshold for recovery purposes.

Scope#

(a) Repository:memora-halborn

(b) Assessed Commit ID:https://github.com/rwishnow-memora/memora-halborn/tree/e9f2daa5a3d9ddc92377a863ab69bc26d064124d

7 files

src

5 files

error.rs

rust

instruction.rs

rust

lib.rs

rust

processor.rs

rust

state.rs

rust

Cargo.toml

toml

rust-toolchain.toml

toml

(a) Submitted File: memora-halborn-e9f2daa5a3d9ddc92377a863ab69bc26d064124d.zip

(b) Items in scope:

8 files

memora-halborn-e9f2daa5a3d9ddc92377a863ab69bc26d064124d / program

8 files

src

5 files

error.rs

rust

instruction.rs

rust

lib.rs

rust

processor.rs

rust

state.rs

rust

Cargo.lock

Cargo.toml

toml

rust-toolchain.toml

toml

a34e7efae7a917f9fc89bcb8769d3cc711c37283 c3316eaf12b90ecc576a553fef705ccba3089c1a 83dd495494f43675ccea6fb23c5013e843319ce9 2b3ac1d77ba76b111e20e2d86c207fd221366166 602b578fd0d7173e099c535a233d84130ade24d5 c798a63ed7b7651b6ef5d3a83111ee0cc9fa66da 0dd4dc61f8db4773b56c0bc3ce355f4bc172a372

Out-of-Scope: New features/implementations after the remediation commit IDs.

Findings Overview#

#	Title	Severity	Score	Status
HAL-01	No instruction exists to rotate the attestor set or threshold after Initialize	Low	4.2	Solved09/05/2026
HAL-02	Weak threshold floor allows a 1-of-N attestor quorum	Low	2.5	Solved09/05/2026
HAL-03	Missing new pause authority validation	Low	2.0	Solved09/05/2026
HAL-04	Missing bridge mint validation	Low	2.0	Solved09/05/2026
HAL-05	Implicit borsh discriminator in BridgeInstruction hardcoded as raw-byte literals	Informational	1.8	Solved09/05/2026
HAL-06	Risk of denial of service after closing the fee or gas ATA	Informational	1.6	Solved09/06/2026
HAL-07	Incomplete accounts builders	Informational	1.3	Solved09/05/2026

Disclaimer#

Halborn strongly recommends conducting a follow-up assessment of the project either within six months or immediately following any material changes to the codebase, whichever comes first. This approach is crucial for maintaining the project’s integrity and addressing potential vulnerabilities introduced by code modifications.