cve.bz

CVE-2018-10657

7.5 highEPSS 1.5%

High (7.5) in matrix synapse. EPSS 1.5% chance of exploitation in the next 30 days. Fixed in matrix-synapse 0.28.1.

Matrix Synapse before 0.28.1 is prone to a denial of service flaw where malicious events injected with depth = 2^63 - 1 render rooms unusable, related to federation/federation_base.py and handlers/message.py, as exploited in the wild in April 2018.

Severity

CVSS 3.0

7.5 high
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.5% chance of exploitation in the next 30 days; higher than 74% of CVEs (scores of 2026-10-31)
CWE
CWE-20
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-vmcc-4p4x-x7wgPyPImatrix-synapse<0.28.10.28.1
PYSEC-2026-846PyPImatrix-synapse<0.28.10.28.1

References

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