In OctoberCMS (october/october composer package) versions from 1.0.319 and before 1.0.466, any users with the ability to modify any data that could eventually be exported as a CSV file from the `ImportExportController` could potentially introduce a CSV injection into the data to cause the generated CSV export file to be malicious. This requires attackers to achieve the following before a successful attack can be completed: 1. Have found a vulnerability in the victims spreadsheet software of choice. 2. Control data that would potentially be exported through the `ImportExportController` by a theoretical victim. 3. Convince the victim to export above data as a CSV and run it in vulnerable spreadsheet software while also bypassing any sanity checks by said software. Issue has been patched in Build 466 (v1.0.466).

Affected: Packagist: october/backend

### Impact Any users with the ability to modify any data that could eventually be exported as a CSV file from the `ImportExportController` could potentially introduce a CSV injection into the data to cause the generated CSV export file to be malicious. This requires attackers to achieve the following before a successful attack can be completed:

1. Have found a vulnerability in the victim's spreadsheet software of choice. 2. Control data that would potentially be exported through the `ImportExportController` by a theoretical victim. 3. Convince the victim to export above data as a CSV and run it in vulnerable spreadsheet software while also bypassing any sanity checks by said software.

### Patches Issue has been patched in Build 466 (v1.0.466).

### Workarounds Apply https://github.com/octobercms/library/commit/c84bf03f506052c848f2fddc05f24be631427a1a & https://github.com/octobercms/october/commit/802d8c8e09a2b342649393edb6d3ceb958851484 to your installation manually if unable to upgrade to Build 466.

### References Reported by @chrisvidal initially & [Sivanesh Ashok](https://stazot.com/) later.

### For more information If you have any questions or comments about this advisory: * Email us at [hello@octobercms.com](mailto:hello@octobercms.com)

### Threat assessment: Given the number of hoops that a potential attacker would have to jump through, this vulnerability really boils down to the possibility of abusing the trust that a user may have in the export functionality of…