
CVE-2023-43796 – Synapse vulnerable to leak of remote user device information
https://notcve.org/view.php?id=CVE-2023-43796
31 Oct 2023 — Synapse is an open-source Matrix homeserver Prior to versions 1.95.1 and 1.96.0rc1, cached device information of remote users can be queried from Synapse. This can be used to enumerate the remote users known to a homeserver. System administrators are encouraged to upgrade to Synapse 1.95.1 or 1.96.0rc1 to receive a patch. As a workaround, the `federation_domain_whitelist` can be used to limit federation traffic with a homeserver. Synapse es un servidor doméstico Matrix de código abierto. • https://github.com/matrix-org/synapse/commit/daec55e1fe120c564240c5386e77941372bf458f • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor •

CVE-2023-45129 – matrix-synapse vulnerable to denial of service due to malicious server ACL events
https://notcve.org/view.php?id=CVE-2023-45129
10 Oct 2023 — Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. Prior to version 1.94.0, a malicious server ACL event can impact performance temporarily or permanently leading to a persistent denial of service. Homeservers running on a closed federation (which presumably do not need to use server ACLs) are not affected. Server administrators are advised to upgrade to Synapse 1.94.0 or later. As a workaround, rooms with malicious server ACL events can be purged and blocked us... • https://github.com/matrix-org/synapse/pull/16360 • CWE-770: Allocation of Resources Without Limits or Throttling •

CVE-2023-41335 – Temporary storage of plaintext passwords during password changes in matrix synapse
https://notcve.org/view.php?id=CVE-2023-41335
26 Sep 2023 — Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. When users update their passwords, the new credentials may be briefly held in the server database. While this doesn't grant the server any added capabilities—it already learns the users' passwords as part of the authentication process—it does disrupt the expectation that passwords won't be stored in the database. As a result, these passwords could inadvertently be captured in database backups for a longer durati... • https://github.com/matrix-org/synapse/pull/16272 • CWE-312: Cleartext Storage of Sensitive Information •

CVE-2023-42453 – Improper validation of receipts allows forged read receipts in matrix synapse
https://notcve.org/view.php?id=CVE-2023-42453
26 Sep 2023 — 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. • https://github.com/matrix-org/synapse/pull/16327 • CWE-285: Improper Authorization •

CVE-2023-32683 – URL deny list bypass via oEmbed and image URLs when generating previews in Synapse
https://notcve.org/view.php?id=CVE-2023-32683
06 Jun 2023 — Synapse is a Matrix protocol homeserver written in Python with the Twisted framework. A discovered oEmbed or image URL can bypass the `url_preview_url_blacklist` setting potentially allowing server side request forgery or bypassing network policies. Impact is limited to IP addresses allowed by the `url_preview_ip_range_blacklist` setting (by default this only allows public IPs) and by the limited information returned to the client: 1. For discovered oEmbed URLs, any non-JSON response or a JSON response whic... • https://github.com/matrix-org/synapse/pull/15601 • CWE-863: Incorrect Authorization CWE-918: Server-Side Request Forgery (SSRF) •

CVE-2023-32682 – Improper checks for deactivated users during login in synapse
https://notcve.org/view.php?id=CVE-2023-32682
06 Jun 2023 — Synapse is a Matrix protocol homeserver written in Python with the Twisted framework. In affected versions it may be possible for a deactivated user to login when using uncommon configurations. This only applies if any of the following are true: 1. JSON Web Tokens are enabled for login via the `jwt_config.enabled` configuration setting. 2. The local password database is enabled via the `password_config.enabled` and `password_config.localdb_enabled` configuration settings *and* a user's password is updated v... • https://github.com/matrix-org/synapse/pull/15624 • CWE-287: Improper Authentication •

CVE-2022-39374 – Synapse Denial of service due to incorrect application of event authorization rules during state resolution
https://notcve.org/view.php?id=CVE-2022-39374
26 May 2023 — Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. If Synapse and a malicious homeserver are both joined to the same room, the malicious homeserver can trick Synapse into accepting previously rejected events into its view of the current state of that room. This can be exploited in a way that causes all further messages and state changes sent in that room from the vulnerable homeserver to be rejected. This issue has been patched in version 1.68.0 Synapse es un se... • https://github.com/matrix-org/synapse/pull/13723 • CWE-400: Uncontrolled Resource Consumption •

CVE-2022-39335 – Synapse does not apply enough checks to servers requesting auth events of events in a room
https://notcve.org/view.php?id=CVE-2022-39335
26 May 2023 — Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix Federation API allows remote homeservers to request the authorization events in a room. This is necessary so that a homeserver receiving some events can validate that those events are legitimate and permitted in their room. However, in versions of Synapse up to and including 1.68.0, a Synapse homeserver answering a query for authorization events does not sufficiently check that the requesting server s... • https://github.com/matrix-org/synapse/issues/13288 • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor CWE-862: Missing Authorization •

CVE-2023-32323 – Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites
https://notcve.org/view.php?id=CVE-2023-32323
26 May 2023 — Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. A malicious user on a Synapse homeserver X with permission to create certain state events can disable outbound federation from X to an arbitrary homeserver Y. Synapse instances with federation disabled are not affected. In versions of Synapse up to and including 1.73, Synapse did not limit the size of `invite_room_state`, meaning that it was possible to create an arbitrarily large invite event. Synapse 1.74 refu... • https://github.com/matrix-org/synapse/issues/14492 • CWE-20: Improper Input Validation •

CVE-2022-41952 – Uncontrolled Resource Consumption in Matrix Synapse
https://notcve.org/view.php?id=CVE-2022-41952
22 Nov 2022 — Synapse before 1.52.0 with URL preview functionality enabled will attempt to generate URL previews for media stream URLs without properly limiting connection time. Connections will only be terminated after `max_spider_size` (default: 10M) bytes have been downloaded, which can in some cases lead to long-lived connections towards the streaming media server (for instance, Icecast). This can cause excessive traffic and connections toward such servers if their stream URL is, for example, posted to a large room w... • https://github.com/matrix-org/synapse/pull/11784 • CWE-400: Uncontrolled Resource Consumption CWE-772: Missing Release of Resource after Effective Lifetime •