Plane is an open-source project management tool. Prior to 1.4.0, IntakeIssuePublicViewSet.create in Plane v1.3.1 writes description_html through Issue.objects.create(...) without calling validate_html_content from nh3. Any authenticated user, including a new user with no workspace memberships, can plant arbitrary HTML in a project that has a published DeployBoard with intake enabled. When a project member or viewer of a closed intake item clicks the planted link, the TipTap \tjavascript: parser bypass and the target="_self" click handler execute JavaScript in the viewer's session and exfiltrate a long-lived API token. This issue is fixed in 1.4.0.
Exploitability
AV:NAC:LPR:LUI:RScope
S:CImpact
C:HI:HA:N8.7/CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:NAccess Control
Injection