CVE-2026-86283 MISP UiBeta Collection View Bypasses Event ACL, Exposing Unauthorized Event Data
Authenticated users can bypass event access controls in MISP's UiBeta theme to view unauthorized event details, leading to horizontal privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-86283?
CVE-2026-86283 is a high-severity missing authorization vulnerability in MISP, published on 6 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
MISP's UiBeta theme collection view (app/View/Themed/UiBeta/Collections/view.ctp) performed a secondary query of member events by UUID without applying the caller's access control list (ACL). The CollectionsController::view() action correctly resolved collection element UUIDs through Event::fetchSimpleEvents($user, ...), which enforces per-user event ACL. However, the view template independently re-queried the same UUIDs using only an Event.uuid IN (...) condition, omitting the createEventConditions() authorization filter. Because collection element UUIDs are stored without server-side authorization against the referenced event (CollectionElementsController::add() accepts whatever UUID the collection owner posts), an authenticated user with view access to a collection could retrieve full details of events they are not permitted to read. The exposed data included event identifiers, info, dates, timestamps, creator organization, all event tags, and galaxy clusters (the latter attached via a cluster-scoped rather than event-scoped ACL check). This constitutes an authorization bypass at the presentation layer, allowing horizontal privilege escalation across event boundaries within the MISP instance.
Which versions are affected by CVE-2026-86283?
How do I fix CVE-2026-86283?
No fix has been published for CVE-2026-86283 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-86283 being exploited?
There is no known exploitation of CVE-2026-86283 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-p286-r3vc-q86q.