CVE-2026-43887

HIGH

Outline: Stored XSS via Comment Mentions

Title source: cna
STIX 2.1

Description

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.

References (1)

Core 1
Core References

Scores

CVSS v3 7.3
EPSS 0.0024
EPSS Percentile 15.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact total

Details

CWE
CWE-79
Status published
Products (1)
outline/outline >= 0.84.0, < 1.7.0
Published May 11, 2026
Tracked Since May 12, 2026