Summary

launch-editor forwarded file paths directly to editors without sanitization. If a path resembles a CLI flag, editors like Vim may interpret it as a command, potentially causing unintended file overwrites or command execution.

Impact

Direct launch-editor users

Only apps that match all of the following conditions are affected:

- The attacker is able to create a file system entry (e.g. a file or directory) starting with + or - in the working directory - The user uses or the app specifies any of the following editors: - Vim (including gVim) - MacVim - Emacs (including Emacsclient) - Notepad++ (only if using a plugin exposing dangerous operations via plugin messages) - The first argument of launchEditor can start with + or - or the user is using WSL

launch-editor-middleware users

Only apps that match the following conditions are affected:

- The attacker is able to create a file system entry (e.g. a file or directory) starting with + or - in the working directory - The user uses or the app specifies any of the following editors: - Vim (including gVim) - MacVim - Emacs (including Emacsclient) - Notepad++ (only if using a plugin exposing dangerous operations via plugin messages) - launch-editor older than v2.2.0 is used, or the user is using WSL

Vite users

Only apps that match the following conditions are affected:

- The attacker is able to create a file system entry (e.g. a file or directory) starting with + or - in the working directory - The user uses or the app specifies any of the following editors: - Vim (including gVim) - MacVim - Emacs (including Emacsclient) - Notepad++ (only if using a plugin exposing dangerous operations via plugin messages) - The user is using WSL

Details

launchEditor(file) function passes the file name as-is to the editor if the file with that file name exists. If the file name starts with - (also + for Vim), the editor treats them as flags rather than positional arguments. For example, Vim treats arguments starting with + as an Ex command. As a result, an existing relative directory such as: +call writefile(["SAFEMARKER"],"LAUNCHEDITORMARKER")|qa! is not treated as a filename when passed to Vim. Vim executes the embedded Ex command.

The following editor has a potentially destructive operation exposed to the CLI arguments: - Vim (including gVim) - MacVim - Emacs (including Emacsclient) - Notepad++ (only if using a plugin exposing dangerous operations via plugin messages)

launch-editor-middleware v2.2.0+ converts the passed file path to an absolute path so those are not affected as long as the user is not using WSL. For WSL, launch-editor converts the paths to relative paths internally, so those are still affected.

Vite 2.0.0+ uses launch-editor-middleware v2.2.0+ so the WSL users are only affected.

Summary

launch-editor did not escape % on Windows when passing an argument to cmd. When an environment variable contained a malicious value, it was possible that that content to be executed.

Impact

Only apps that match all of the following conditions are affected:

- The user uses Windows - An attacker can place a file with the malicious filename containing & or % - Either of - An attacker can inject an environment variable with a malicious value - An attacker can add a NTFS alternate data stream to the file placed

Details

Unlike .sh files, .bat / .cmd files on Windows cannot be called directly using childprocess.spawn and requires passing them as an argument of cmd.exe. To do so, launch-editor escapes the arguments passed to cmd.exe. But launch-editor did not escape % which is used for environment variables.

Because launch-editor checks if the argument matches an existing filename, the attack requires the attacker to be able to place a file.

- If the attacker can inject an environment variable as well, they can include the subcommand in the env variable (e.g. set &calc.exe to %ENV%) and call launchEditor with something%ENV%. - If the attacker can place a NTFS alternate data stream to the file (e.g. a NTFS alternate data stream named ~-38%calc.exe), they can call launchEditor with something %CMDCMDLINE:~-38%calc.exe. - If the attacker can create a filename containing the %CD% and the subcommand (e.g. &calc.exe ), they can call launchEditor with ./%CD%

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.

launch-editor allows users to open files with line numbers in editor from Node.js. Prior to version 2.9.0, due to the insufficient sanitization of the file argument in the launchEditor, an attacker can execute arbitrary commands on Windows by supplying a filename that contains special characters. This issue has been fixed in the launch-editor version 2.9.0, corresponding to vite version 5.4.9.

Summary Due to the insufficient sanitization of the file argument in the launchEditor, an attacker can execute arbitrary commands on Windows by supplying a filename that contains special characters.

Impact If the following conditions are met, an attacker can execute arbitrary commands on the computer that is using the launch-editor:

- An attacker can place a file with the malicious filename - An attacker can call the launchEditor method with the file argument controlled - The launch-editor package is running on Windows

For example, some development server using this package satisfy these conditions, as a malicious website might be able to force the downloading of a file and the path of that file is predictable.

Patch This issue has been fixed in the launch-editor version 2.9.0 (commit).