GHSA-49mj-x8jp-qvfc OctoPrint is Vulnerable to RCE Attacks via Unsanitized Filename in File Upload

• PyPI octoprint: < 1.11.3 → fixed in 1.11.3

Impact OctoPrint versions up until and including 1.11.2 contain a vulnerability that allows an authenticated attacker to upload a file under a specially crafted filename that will allow arbitrary command execution if said filename becomes included in a command defined in a system event handler and said event gets triggered. If no event handlers executing system commands with uploaded filenames as parameters have been configured, this vulnerability does not have an impact. Patches The vulnerability will be patched in version 1.11.3. Workaround Until the patch has been applied, OctoPrint administrators who have event handlers configured that include any kind of filename based placeholders (i.e. `{__filename}`, `{__filepath}`, `{filename}`, `{path}`, etc -- refer to the events documentation for a full list) should disable those by setting their `enabled` property to `False` or unchecking the "Enabled" checkbox in the GUI based Event Manager. Alternatively, OctoPrint administrators should set `feature.enforceReallyUniversalFilenames` to `true` in `config.yaml` and restart OctoPrint, then vet the existing uploads and make sure to delete any suspicious looking files (e.g. those that contain a `;` in their name followed by a command). As always, OctoPrint administrators are advised to not expose OctoPrint on hostile networks like the public internet, and to vet who has access to their instance. Credits This vulnerability was discovered and responsibly disclosed to OctoPrint by @prabhatverma47.