Shescape

Shescape is a simple shell escape package for JavaScript. Affected versions were found to have insufficient escaping of white space when interpolating output. This issue only impacts users that use the `escape` or `escapeAll` functions with the `interpolation` option set to `true`. The result is that if an attacker is able to include whitespace in their input they can: 1. Invoke shell-specific behaviour through shell-specific special characters inserted directly after whitespace. 2. Invoke shell-specific behaviour through shell-specific special characters inserted or appearing after line terminating characters. 3. Invoke arbitrary commands by inserting a line feed character. 4. Invoke arbitrary commands by inserting a carriage return character. Behaviour number 1 has been patched in [v1.5.7] which you can upgrade to now. No further changes are required. Behaviour number 2, 3, and 4 have been patched in [v1.5.8] which you can upgrade to now. No further changes are required. The best workaround is to avoid having to use the `interpolation: true` option - in most cases using an alternative is possible, see [the recipes](https://github.com/ericcornelissen/shescape#recipes) for recommendations. Alternatively, users may strip all whitespace from user input. Note that this is error prone, for example: for PowerShell this requires stripping `'\u0085'` which is not included in JavaScript's definition of `\s` for Regular Expressions.

Published: 2022-08-01T19:15:16.000Z
Updated: 2025-04-22T17:46:22.040Z

Shescape is a simple shell escape package for JavaScript. Versions prior to 1.5.8 were found to be subject to code injection on windows. This impacts users that use Shescape (any API function) to escape arguments for cmd.exe on Windows An attacker can omit all arguments following their input by including a line feed character (`'\n'`) in the payload. This bug has been patched in [v1.5.8] which you can upgrade to now. No further changes are required. Alternatively, line feed characters (`'\n'`) can be stripped out manually or the user input can be made the last argument (this only limits the impact).

Published: 2022-08-01T19:20:18.000Z
Updated: 2025-04-22T17:46:08.799Z