cve.bz

CVE-2018-12423

7.5 highEPSS 1.8%

High (7.5) in matrix synapse. EPSS 1.8% chance of exploitation in the next 30 days. Fixed in matrix-synapse 0.31.2.

In Synapse before 0.31.2, unauthorised users can hijack rooms when there is no m.room.power_levels event in force.

Severity

CVSS 3.0

7.5 high
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
1.8% chance of exploitation in the next 30 days; higher than 78% of CVEs (scores of 2026-10-31)
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-ch5v-fhg8-7gv9PyPImatrix-synapse<0.31.20.31.2
PYSEC-2026-844PyPImatrix-synapse<0.31.20.31.2

References

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