OpenSlides is a free, Web-based presentation and assembly system for managing and projecting agenda, motions, and elections of assemblies. OpenSlides version 3.2, due to unsufficient user input validation and escaping, it is vulnerable to persistant cross-site scripting (XSS). In the web applications users can enter rich text in various places, e.g. for personal notes or in motions. These fields can be used to store arbitrary JavaScript Code that will be executed when other users read the respective text. An attacker could utilize this vulnerability be used to manipulate votes of other users, hijack the moderators session or simply disturb the meeting. The vulnerability was introduced with 6eae497abeab234418dfbd9d299e831eff86ed45 on 16.04.2020, which is first included in the 3.2 release. It has been patched in version 3.3 ( in commit f3809fc8a97ee305d721662a75f788f9e9d21938, merged in master on 20.11.2020).
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
| Link | Tags |
|---|---|
| https://github.com/OpenSlides/OpenSlides/security/advisories/GHSA-w5wr-98qm-jx92 | third party advisory |
| https://github.com/OpenSlides/OpenSlides/pull/5714 | third party advisory patch |
| https://github.com/OpenSlides/OpenSlides/commit/f3809fc8a97ee305d721662a75f788f9e9d21938 | third party advisory patch |
| https://github.com/OpenSlides/OpenSlides/blob/master/CHANGELOG.rst#version-33-2020-12-18 | third party advisory release notes |
| https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2020-043.txt | broken link |