cve.bz

CVE-2023-42453

4.3 mediumEPSS 0.8%

Medium (4.3). EPSS 0.8% chance of exploitation in the next 30 days. Fixed in matrix-synapse 1.93.0.

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. Users were able to forge read receipts for any event (if they knew the room ID and event ID). Note that the users were not able to view the events, but simply mark it as read. This could be confusing as clients will show the event as read by the user, even if they are not in the room. This issue has been patched in version 1.93.0. Users are advised to upgrade. There are no known workarounds for this issue.

Severity

CVSS 3.1

4.3 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
EPSS
0.8% chance of exploitation in the next 30 days; higher than 55% of CVEs (scores of 2026-10-31)
CWE
CWE-285
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-7565-cq32-vx2xPyPImatrix-synapse>=0.34.0 <1.93.01.93.0
PYSEC-2023-180PyPImatrix-synapse>=1.34.0 <1.93.01.93.0

References

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