CVE-2023-42453

Improper validation of receipts allows forged read receipts in matrix synapse

State
Published
Severity
3.1 Low
Published
Sep 26, 2023
Updated
Jun 18, 2025
Reserved
Sep 8, 2023

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.13.1 LowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:NGitHub_M

Weaknesses

Affected Products

ProductVersions
synapsematrix-org
  • >= 0.34.0, < 1.93.0Affected

References

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