CVE-2026-43887
HighSummary
Outline is a service that allows for collaborative documentation. From versions 0.84.0 to 1.6.1, the comment section permits users to mention other users; however, the backend does not validate or sanitize the href attribute associated with these mentions, potentially leading to client-side code execution.
Risk Assessment
The lack of validation on the href attribute poses a risk of executing malicious code, which could compromise user data and sessions. Organizations should be aware of potential attacks exploiting this vulnerability.
Recommendation
It is recommended to upgrade to version 1.7.0 or later to mitigate this vulnerability. Additionally, conducting a security audit of the application to identify other potential flaws is advisable.
Other vulnerabilities in Outline
See all- CVE-2026-43886High
Outline is a service that allows for collaborative documentation. From versions 0.84.0 to 1.6.1, a logic error in OAuthInterface.validateScope() allows the entire scope array to be accepted if any single scope is valid.
- CVE-2026-41649High
Outline versions 0.86.0 through 1.7.0 contain an insecure direct object reference (IDOR) vulnerability in the `shares.create` API endpoint. When both `collectionId` and `documentId` are provided in the request, the authorization logic only checks access to the collection, ignoring the document. This allows an authenticated attacker to generate a valid public share link for any document on the platform, including documents from other workspaces.
Original NVD description (English source)
Outline is a service that allows for collaborative documentation. From 0.84.0 to 1.6.1, the Outline comment section permits users to mention other users; however, the backend does not validate or sanitize the href attribute associated with these mentions. As a result, potentially dangerous protocols (e.g., javascript:) are not filtered, introducing a risk of client-side code execution. This vulnerability is fixed in 1.7.0.