Improper validation of receipts allows forged read receipts in matrix synapse
CVE-2023-42453

3.1LOW

Key Information:

Vendor

Matrix-org

Status
Synapse
Vendor
CVE Published:
27 September 2023

What is CVE-2023-42453?

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.

Affected Version(s)

synapse >= 0.34.0, < 1.93.0

References

https://github.com/matrix-org/synapse/security/advisories...
x_refsource_CONFIRM
https://github.com/matrix-org/synapse/pull/16327
x_refsource_MISC
https://lists.fedoraproject.org/archives/list/package-ann...

CVSS V3.1

Score:
3.1
Severity:
LOW
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.