GHSA-587h-7wmj-h5pm launch-editor: `fs.existsSync()` existence check can be bypassed on Windows

• npm launch-editor: < 2.14.2 → fixed in 2.14.2 • npm vite: >= 8.3.0, < 8.3.3 → fixed in 8.3.3 • npm vite: >= 8.2.0, < 8.2.4 → fixed in 8.2.4 • npm vite: >= 8.0.0, < 8.1.6 → fixed in 8.1.6 • npm vite: >= 7.0.0, < 7.3.7 → fixed in 7.3.7 • npm vite: < 6.4.4 → fixed in 6.4.4 • npm vite-plus: < 1.1.0 → fixed in 1.1.0

Summary `launch-editor` checked `fs.existsSync(fileName)` before passing a supplied path to an editor command. On Windows, an attacker can bypass this check with a crafted path ending in `\\..:line:column`. This removes the requirement that the attacker be able to place a file with a malicious filename. Combined with the `%` escaping issue described in GHSA-698v-4r3x-3vcv, this bypass can lead to OS command injection when an attacker controls the file argument. Impact Only apps that runs on Windows is affected. Details The earlier advisory assumed that `fs.existsSync()` required an attacker-controlled filename to exist. This advisory covers a bypass of that requirement. A crafted value ending in `\\..:1:1` is interpreted differently by `launch-editor-middleware`, `launch-editor`, and Windows: 1. `launch-editor-middleware` calls `path.resolve()` while the final path component is `..:1:1`, so it is not treated as a parent-directory component. 2. `launch-editor` treats `:1:1` as a line-and-column suffix and removes it, leaving a path ending in `\\..`. 3. On Windows, `fs.existsSync()` accepts the resulting path as the existing parent directory even though the attacker-controlled preceding component does not exist. 4. Because the existence check passes, the crafted filename reaches the Windows shell command.