Login Request a demo
Medium severity · published Sep 26, 2023
CVE-2023-42453
Improper validation of receipts allows forged read receipts in matrix synapse
4.3
CVSS
0.8%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SY
synapse · matrix-org
>= 0.34.0, < 1.93.0 · source: vendor, NVD
FE
Fedora · Fedoraproject
37; 38 · source: NVD
Affected product
SY
synapse
matrix-org
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-42453
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-42453
Issue Tracking
https://github.com/matrix-org/synapse/pull/16327
Vendor Advisory
https://github.com/matrix-org/synapse/security/advisories/GHSA-7565-cq32-vx2x
Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2AFB2Y3S2VCPCN5P2XCZTG24MBMZ7DM4/
Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/65QPC55I4D27HIZP7H2NQ34EOXHPP4AO/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/N6P4QULVUE254WI7XF2LWWOGHCYVFXFY/
security.gentoo.org
https://security.gentoo.org/glsa/202401-12
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