Description
The Matrix specification before 1.16 (i.e., with a room version before 12) lacks create event uniqueness.
References2
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:L - EPSS — exploit probability
- 0% percentile: 27 · as of 9 November 2026
- CWE
- CWE-837
Could this be exploited in your environment?
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