CVE-2020-5299: Potential CSV Injection vector in OctoberCMS

Severity: medium (CVSS 5.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-06-03 · updated 2026-06-17
Weakness: CWE-77

Description

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 products

octobercms october: from 1.0.319 before 1.0.466 — fixed in 1.0.466

How to fix

Upgrade to a fixed version: octobercms october 1.0.466. Check the vendor advisory for mitigations.

References

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