Named path parameters can be overridden in TrieRouter

### Impact The clients may override named path parameter values from previous requests if the application is using TrieRouter. So, there is a risk that a privileged user may use unintended parameters when deleting REST API resources. TrieRouter is used either explicitly or when the application matches a pattern that is not supported by the default RegExpRouter. The code to reproduce it. The server side application: ```ts import { Hono } from 'hono' import { TrieRouter } from 'hono/router/trie-router' const wait = async (ms: number) => { return new Promise((resolve) => { setTimeout(resolve, ms) }) } const app = new Hono({ router: new TrieRouter() }) app.use('*', async (c, next) => { await wait(Math.random() * 200) return next() }) app.get('/modules/:id/versions/:version', async (c) => { const id = c.req.param('id') const version = c.req.param('version') console.log('path', c.req.path) console.log('version', version) return c.json({ id, version, }) }) export default app ``` The client code which makes requests to the server application: ```ts const examples = [ 'http://localhost:8787/modules/first/versions/first', 'http://localhost:8787/modules/second/versions/second', 'http://localhost:8787/modules/third/versions/third', ] const test = () => { for (const example of examples) { fetch(example) .then((response) => response.json()) .then((data) => { const splitted = example.split('/') const expected = splitted[splitted.length - 1] if (expected !== data.version) { console.error(`Error: exprected ${expected} but got ${data.version} - url was ${example}`) } }) } } test() ``` The results: ```txt Error: exprected second but got third - url was http://localhost:8787/modules/second/versions/second Error: exprected first but got third - url was http://localhost:8787/modules/first/versions/first ``` ### Patches "v3.11.7" includes the change to fix this issue. ### Workarounds Don't use TrieRouter directly. ```ts // DON'T USE TrieRouter import { TrieRouter } from 'hono/router/trie-router' const app = new Hono({ router: new TrieRouter() }) ``` ### References Router options on the Hono website: https://hono.dev/api/hono#router-option

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