Build Cross-Chain Bridge and Message Verification Vulnerability Rules

[Nanle-code]

Summary

Implement a production-grade cross-chain bridge and message verification vulnerability rules for StellarChainproofs/ChainProof. This issue is a complete engineering track rather than a narrow detector patch: it requires durable TypeScript architecture, integrated workflows, comprehensive validation, tests, fixtures, and documentation.

Problem statement

Bridge and messaging contracts rely on domain separation, replay protection, validator thresholds, proof verification, ordering, and finality assumptions that general call analysis does not capture.

Required scope

• Model outbound messages, inbound verification, domains, nonces, roots, validator sets, thresholds, finality windows, and execution state.
• Detect missing source or destination binding, replayable messages, nonce collisions, weak threshold transitions, and verification bypasses.
• Analyze proof and signature loops for duplicate validators, unsorted sets, zero-address members, stale roots, and unsafe quorum arithmetic.
• Trace message payloads into privileged calls, token minting, release, upgrades, and arbitrary execution.
• Recognize pause, rate-limit, replay-map, two-phase validator update, and delayed-finality mitigations.
• Test lock/mint and burn/release bridges, optimistic messages, multisig validators, Merkle proofs, relayer retries, and secure reference fixtures.

Acceptance criteria

• The capability is exposed through coherent @chainproof/core APIs and appropriate CLI, server, editor, action, or plugin surfaces with stable versioned output.
• Analysis behavior is deterministic by default, bounded against adversarial input, and accompanied by precise source locations, evidence paths, assumptions, and confidence where applicable.
• Core logic is separated from transport and presentation layers and does not require external network services in CI.
• New configuration, caches, databases, manifests, or report formats are versioned and include validation, migration, and corruption handling.
• Errors preserve actionable context without leaking source, credentials, local paths, provider data, or other sensitive information.
• Tests include vulnerable and secure fixtures, false-positive controls, malformed input, boundary conditions, failure recovery, and performance safeguards.
• Public APIs and CLI behavior are documented with security assumptions, compatibility constraints, examples, and operational troubleshooting.

Required deliverables

• Production TypeScript implementation placed in the appropriate packages/core, packages/cli, packages/server, packages/vscode-extension, packages/github-action, or clearly justified new workspace package.
• Typed public interfaces, structured diagnostics, deterministic serialization, resource limits, cancellation, and recovery behavior appropriate to the feature.
• Unit, integration, CLI, adversarial, and regression tests plus vulnerable and secure Solidity fixtures or protocol test doubles.
• Documentation for users, rule authors, integrators, and maintainers, including threat model, limitations, compatibility, migration, and troubleshooting.
• A pull-request description explaining architecture, precision/recall considerations, security boundaries, performance measurements, test evidence, and follow-up work.

Integration boundaries

This static rule pack does not provide on-chain monitoring or duplicate AI multi-contract analysis in #61.

Avoid unrelated rewrites, placeholder detectors, hidden live-network dependencies, dead code, and changes that weaken existing rules, type safety, security controls, or test coverage.

Minimum implementation requirement

This is intentionally a substantial contributor project. A mergeable pull request must add at least 1,000 lines of meaningful production implementation code for this issue. The minimum excludes tests, documentation, comments-only changes, generated output, vendored code, Solidity fixtures, snapshots, lockfiles, formatting-only churn, and unrelated refactors. Do not pad the implementation to reach the threshold; the required behavior must justify the code through cohesive, maintainable functionality.

CI and conflict-free merge gate

A pull request must not be merged until every required CI check passes on the final commit. At minimum, contributors must preserve a green result for the repository's applicable gates:

• npm ci
• npm run lint
• npm run build
• npm run test
• npm run test:ci --workspace=packages/core
• Package-specific build and test commands for every affected workspace
• The existing ChainProof audit workflow and API documentation build when applicable

Any new workspace, command, detector, report format, plugin capability, server route, compiler adapter, or CI provider integration requires targeted automated coverage. Contributors may not disable tests, relax type or lint rules, reduce coverage, suppress legitimate failures, or alter CI merely to obtain a passing result.

The final PR branch must be updated against the target branch and have no merge conflicts. If rebasing or updating changes the final commit, all required CI checks must run again and pass before merge.

[Santia2004]

Hi! I would like to work on this issue. I have solid experience with TypeScript/JavaScript, backend architectures, and Soroban/Stellar integrations, and I have recently contributed clean, merged implementations across campaign repositories. Please feel free to assign it to me. Thanks!

[tunmisedasa]

Hi, I’d like to take on this issue.

This is a substantial engineering task, and I understand that the goal is not simply to add a few pattern-matching detectors, but to build a production-grade cross-chain bridge and message verification analysis capability that fits cleanly into the existing ChainProof architecture.

My proposed approach would be to first study the existing @chainproof/core analysis pipeline, rule architecture, diagnostic/reporting models, workspace boundaries, and existing integration surfaces before making implementation decisions. I would keep the core bridge-analysis logic independent from the CLI, server, editor, GitHub Action, or other presentation layers, then expose the capability through the appropriate existing interfaces.

The implementation would focus on modeling the security-critical state and data flows involved in cross-chain messaging, including domains, source and destination bindings, nonces, message identifiers, replay state, roots, validator sets, thresholds, finality assumptions, proof verification, and execution state.

I would specifically investigate and implement detection coverage for issues such as:

• Missing source-chain, destination-chain, or domain binding
• Replayable messages and incomplete replay protection
• Nonce reuse, collisions, or unsafe message identity construction
• Verification and authorization bypasses
• Duplicate or invalid validators in proof/signature verification
• Unsorted or malformed validator sets where ordering assumptions affect verification
• Zero-address or otherwise invalid validator members
• Weak quorum and threshold arithmetic, including unsafe threshold transitions
• Stale or improperly bound roots
• Proof validation weaknesses
• Unsafe validator-set updates
• Payloads flowing from bridge/message verification into privileged execution, token minting, asset release, upgrades, or arbitrary calls

I would also model common mitigations so the rules can distinguish vulnerable implementations from intentionally protected designs, including replay maps, pause mechanisms, rate limits, delayed finality, two-phase validator updates, and related security controls. Precision and false-positive control would be a major consideration rather than treating the presence of any privileged bridge flow as automatically vulnerable.

For validation, I would add both vulnerable and secure fixtures covering lock/mint and burn/release bridges, optimistic messaging, multisig validator verification, Merkle-proof flows, relayer retries, and important edge cases. I would also include malformed and adversarial inputs, boundary conditions, regression coverage, failure-recovery scenarios, and performance/resource-limit tests where applicable.

I understand the minimum requirement of 1,000 lines of meaningful production implementation code and would approach the work as a cohesive feature rather than padding the contribution or introducing placeholder detectors. The architecture and required behavior should naturally justify the implementation size.

Before submitting the PR, I would ensure that the affected workspace tests and repository gates pass, including linting, builds, tests, core CI coverage, and any package-specific checks required by the implementation. I would also keep the branch updated against the target branch and resolve merge conflicts before requesting review.

I would document the threat model, security assumptions, known limitations, compatibility constraints, public APIs, rule-author guidance, integration behavior, migration considerations, and troubleshooting. The final PR description would also include the architectural decisions, precision/recall tradeoffs, security boundaries, performance results, test evidence, and any reasonable follow-up work.

My background and current interests are strongly aligned with this type of contribution. I work across systems and protocol engineering, distributed systems, networking, blockchain infrastructure, and security analysis, and I’m particularly interested in understanding and modeling protocol state transitions, verification logic, trust boundaries, and adversarial edge cases.

If the issue is available, I’d appreciate the opportunity to be assigned to it. I’m prepared to approach it as a substantial production contribution and work within the repository’s existing architecture and engineering standards.

[grantfox-oss]

🦊 GrantFox — @tunmisedasa has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #83)
2. Your PR will be reviewed by the StellarChainproof maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Third Campaign campaign!

@tunmisedasa's PR #109 was approved and merged by @Nanle-code.

🏆 @tunmisedasa: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (48 total points). Track your full progress on GrantFox.

👏 Great work, @tunmisedasa! Keep contributing to StellarChainproof.