Bug 2242239 (CVE-2023-42453)

Summary:	CVE-2023-42453 matrix-synapse: improper validation of receipts allows forged read receipts
Product:	[Other] Security Response	Reporter:	TEJ RATHI <trathi>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	Keywords:	Security
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	matrix-synapse 1.93.0	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2242241
Bug Blocks:

Description TEJ RATHI 2023-10-05 06:10:57 UTC

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.

https://github.com/matrix-org/synapse/security/advisories/GHSA-7565-cq32-vx2x
https://github.com/matrix-org/synapse/pull/16327

Comment 1 TEJ RATHI 2023-10-05 06:11:52 UTC

Created matrix-synapse tracking bugs for this issue:

Affects: fedora-all [bug 2242241]