CVE-2025-58351: Getoutline Outline

Medium severity, CVSS 6.8. EPSS: 0.4% chance of exploitation in the next 30 days.

Outline is a service that allows for collaborative documentation. In versions 0.72.0 through 0.83.0, Outline introduced a feature which facilitates local file system storage capabilities as an optional file storage strategy. This feature allowed a CSP bypass as well as a ContentType bypass that might facilitate further attacks. In the case of self-hosting and using Outline FILE_STORAGE=local on the same domain as the Outline application, a malicious payload can be uploaded as a file attachment and bypass those CSP restrictions, allowing script execution within the context of another user. This is fixed in version 0.84.0.

Affected products

• Getoutline Outline: from 0.72.0, before 0.84.0 (fixed in 0.84.0)

Published 2025-09-03. Last modified 2026-06-17.