WASM sandbox
Every module runs in Wasmtime with a 1-billion-instruction fuel cap and a 16 MB memory limit.
// synaps
Synaps WASM modules
Extend the scanner without trusting the code — community modules compiled to WebAssembly and run in a hard sandbox.
// capabilities
What it does
Rust guest SDK
Authors write Rust against hugin-scanner-guest and compile to wasm32 — the SDK is open source.
real capabilities
Modules get HTTP, raw TCP, DNS, TLS inspection, WebSocket, browser automation and Oastify via host imports.
install and run
Pull a community module and run it; the sandbox guarantee means untrusted code can't touch your system.
// detail
Extend the engine, safely
Caido's own security policy says it out loud: its JavaScript plugins have “unrestricted access” — they can read the files on your computer, reach the internet, and “install or execute additional programs,” and that “cannot be fully restricted at this time.” Synaps takes the opposite bet. Every module is WebAssembly in a Wasmtime sandbox with hard, metered limits, so running a stranger’s check can’t cost you your machine.
1-billion-instruction fuel cap
Wasmtime meters every guest opcode. A runaway or hostile loop traps as out-of-fuel — it can't pin a CPU core the way a free-running plugin can.
16 MiB memory ceiling
256 linear-memory pages, hard-capped at instantiation. A module can't balloon and starve the host of RAM.
100 ms epoch deadline
Defense-in-depth over fuel: a guest that burns wall-clock time inside a host call is still cut off, so it can't hang a scan.
Capability-gated host calls
A module reaches HTTP, DNS, TLS, WebSocket, Oastify or a scoped file read only through typed host imports. There is no ambient filesystem and no way to spawn a process.
// more
The rest of the toolkit
Intercepting proxy
Every request your browser makes, on your terms — pause it, rewrite it, release it. HTTP/1.1, HTTP/2, HTTP/3 and WebSocket, with on-the-fly TLS.
Vulnerability scanner
An active and passive scanner that ships free — OWASP and API Top 10, with blind out-of-band detection.
Repeater
Send it once. Change one field. Send it again. The careful, hand-driven probe — request and response side by side, over and over.
Intruder
Automated payload attacks at full speed — four modes, 21 generators, 32 processors, and a Turbo mode with raw-TCP batching.
AI agent & MCP
Set a budget, hit explore, and an autonomous agent drives every tool over 162 MCP tools — or wire Claude Code, Cursor or your own agent straight in.
Race conditions PRO
Beat check-then-act windows the proxy can't reach — single-packet attacks, last-byte sync and barrier coordination.