Description (CNA)
Dendrite through 0.13.8 contains an improper access control vulnerability in the syncapi /context endpoint (syncapi/routing/context.go) that allows authenticated local users to access post-leave room state events by exploiting a flawed membership check that evaluates only the RoomExists field while ignoring IsInRoom, HasBeenInRoom, and Membership fields. Attackers who have left a room can call the rooms context API endpoint for a previously permitted event and receive unfiltered current room state that the /messages and /sync endpoints correctly withhold.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| matrix-org / dendrite | affected 0 through 0.13.8 |
CWE
CWE-863
References
- https://github.com/geo-chen/oss/blob/main/dendrite.md#finding-3-context-returns-current-room-state-to-non-members-and-left-users-history-visibility-bypass
- https://www.vulncheck.com/advisories/dendrite-syncapi-context-endpoint-post-leave-state-exposure
ADP enrichment
No English description supplied.
No references supplied.