CVE-2026-104979 HIGH

CVE-2026-104979: Plane: Cross-tenant stored XSS in intake enables account takeover

Vendor Makeplane
Product plane
Weakness CWE-79 · XSS
Published October 5, 2026
Last update October 5, 2026

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction Required
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

October 5, 2026 CVE published

Related vulnerabilities

04Related CVE