Cross-chain security

A bridge or messaging layer asks one chain to act on something that happened on another. Everything depends on the verification step in between, and on each message being accepted exactly once, on exactly one chain.

In this area

Publications: 2
Reading time: 17 min

Primers explain a known class of issue with illustrative code. Analyses synthesise public incidents, standards and papers, each cited.

Publications

2 publications on cross-chain security

These publications cover signature and message replay across chains and contracts, and the containment controls that bound what a single verification failure can take. The incident analysis of public bridge exploits completes the reading list.

Cross-Chain Security31 October 202611 min read
Technical analysis
Containing bridge failures: rate limits, delays and emergency pauses
Assume a bridge’s verification will fail one day. Replay protection, rate limits sized from observed outflows, withdrawal delays and a well-scoped pause decide how much that failure can take, and who pays for it.
Cross-Chain Security1 September 20266 min read
Primer
Signature replay across EVM chains
A signature proves that someone agreed to something. Unless the message says where and how often, it can be presented again on another chain, another contract or another day. The binding fields, and how they fail.