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Product · matrix-org

synapse

24 known vulnerabilities.

synapse at a glance

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24 results · Feed

  • Medium 5.3

    Synapse vulnerable to leak of remote user device information

    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 encourag…

  • Medium 4.9

    matrix-synapse vulnerable to denial of service due to malicious server ACL events

    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 run…

  • Low 3.7

    Temporary storage of plaintext passwords during password changes in matrix synapse

    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 a…

  • Low 3.1

    Improper validation of receipts allows forged read receipts in matrix synapse

    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 mar…

  • Low 3.5

    URL deny list bypass via oEmbed and image URLs when generating previews in Synapse

    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…

  • Medium 5.4

    Improper checks for deactivated users during login in synapse

    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 T…

  • Medium 6.5

    Synapse Denial of service due to incorrect application of event authorization rules during state resolution

    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 …

  • Medium 5.0

    Synapse does not apply enough checks to servers requesting auth events of events in a room

    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 ca…

  • Medium 5.0

    Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites

    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. Syn…

  • Medium 6.5

    Uncontrolled Resource Consumption in Matrix Synapse

    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 down…

  • Medium 6.4

    Synapse vulnerable to denial of service (DoS) due to incorrect application of event authorization rules

    Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix specification specifies a list of [event authorization rules](https://spec.matrix.org/v1.2/rooms/v9/#authorization-rules) which must be checked when de…

  • Medium 6.5

    URL previews can crash Synapse media repositories or Synapse monoliths

    Synapse is an open source home server implementation for the Matrix chat network. In versions prior to 1.61.1 URL previews of some web pages can exhaust the available stack space for the Synapse process due to unbounded recursion. This is sometimes recoverabl…

  • High 7.5

    Path traversal in Matrix Synapse

    Synapse is a package for Matrix homeservers written in Python 3/Twisted. Prior to version 1.47.1, Synapse instances with the media repository enabled can be tricked into downloading a file from a remote server into an arbitrary directory. No authentication is…

  • Low 3.1

    Improper authorisation of /members discloses room membership to non-members

    Matrix is an ecosystem for open federated Instant Messaging and Voice over IP. In versions 1.41.0 and prior, unauthorised users can access the membership (list of members, with their display names) of a room if they know the ID of the room. The vulnerability …

  • Low 3.1

    Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.

    Matrix is an ecosystem for open federated Instant Messaging and Voice over IP. In versions 1.41.0 and prior, unauthorised users can access the name, avatar, topic and number of members of a room if they know the ID of the room. This vulnerability is limited t…

  • Low 3.7

    Denial of service in Matrix Synapse

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.33.2 "Push rules" can specify conditions under which they will match, i…

  • Medium 6.3

    Open redirect via transitional IPv6 addresses on dual-stack networks

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.28.0 requests to user provided domains were not restricted to external …

  • Medium 5.3

    Denial of service (via resource exhaustion) due to improper input validation on groups/communities endpoints

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.28.0 Synapse is missing input validation of some parameters on the endp…

  • Medium 5.3

    Denial of service (via resource exhaustion) due to improper input validation on third-party identifier endpoints

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.28.0 Synapse is missing input validation of some parameters on the endp…

  • Medium 6.1

    HTML injection in email and account expiry notifications

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.27.0, the notification emails sent for notifications for missed message…

  • Medium 6.9

    Cross-site scripting (XSS) vulnerability in the password reset endpoint

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.27.0, the password reset endpoint served via Synapse was vulnerable to …

  • Low 3.1

    Open redirects on some federation and push requests

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.25.0, requests to user provided domains were not restricted to external…

  • Medium 4.3

    Denial of service attack via .well-known lookups

    Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.25.0, a malicious homeserver could redirect requests to their .well-kno…

  • Medium 6.5

    Denial of service attack via incorrect parameters to federation APIs

    Matrix is an ecosystem for open federated Instant Messaging and VoIP. Synapse is a reference "homeserver" implementation of Matrix. A malicious or poorly-implemented homeserver can inject malformed events into a room by specifying a different room id in the p…