GHSA-9hc2-hjx8-q6pv

## Description TidGi Desktop through 0.13.0 contains a critical remote code execution vulnerability exploitable via a single Git repository import. The vulnerability leverages TiddlyWiki's module system, which automatically discovers and executes JavaScript code embedded in `.tid` files placed in the wiki's `tiddlers/` directory: 1. **Auto-loading of `.tid` files** (`src/services/wiki/wikiWorker/loadWikiTiddlersWithSubWikis.ts:59-92`) — when TidGi boots a wiki workspace, `loadWikiTiddlers` reads all `.tid` files from the filesystem and adds them to the wiki store via `wiki.addTiddlers()`. 2. **Automatic module registration** (`node_modules/tiddlywiki/boot/boot.js:2564-2565`) — `defineTiddlerModules()` iterates all tiddlers in the store. Any tiddler with a `module-type` field is passed to `$tw.modules.define()`, registering it as an executable module. 3. **Automatic startup execution** (`node_modules/tiddlywiki/boot/boot.js:2572-2634`) — all registered modules of type `"startup"` are collected and their `exports.startup()` function is called during the boot sequence. When no `platforms` restriction is set, `doesTaskMatchPlatform()` returns `true`, and the startup function executes with full Node.js `require()` access in the Wiki Worker process. The full chain was verified on macOS with TiddlyWiki 5.4.0 and Node.js v26 — `require('child_process').execSync()` successfully executed arbitrary shell commands. ## Affected Product - **Product**: TidGi Desktop - **Vendor**: Lin Onetwo (https://github.com/tiddly-gittly) - **Repository**: https://github.com/tiddly-gittly/TidGi-Desktop - **Affected Versions**: 0.13.0 (latest release) - **Components**: `src/services/wiki/wikiWorker/loadWikiTiddlersWithSubWikis.ts` (tiddler loading), `src/services/wiki/wikiWorker/startNodeJSWiki.ts` (wiki boot), `node_modules/tiddlywiki/boot/boot.js` (TiddlyWiki core — `defineTiddlerModules`, startup dispatch) - **Package**: tidgi (npm) ## Vulnerability Details ### Root Cause 1 — `.tid`