GHSA-5chr-wjw5-3gq4

    Dashboard / Vulnerabilities / GHSA-5chr-wjw5-3gq4

    GHSA-5chr-wjw5-3gq4

    Published: 10 Oct 2023Last Modified: 10 Sept 2026

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

    Details: ### Impact 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. ### Patches Server administrators are advised to upgrade to Synapse 1.94.0 or later. ### Workarounds Rooms with malicious server ACL events can be [purged and blocked](https://matrix-org.github.io/synapse/latest/admin_api/rooms.html#version-2-new-version) using the admin API.

    References: https://github.com/matrix-org/synapse/security/advisories/GHSA-5chr-wjw5-3gq4, https://nvd.nist.gov/vuln/detail/CVE-2023-45129, https://github.com/matrix-org/synapse/pull/16360, https://github.com/matrix-org/synapse/commit/f84da3c32ec74cf054e2fd6d10618aa4997cffaa, https://github.com/matrix-org/synapse, https://github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2023-199.yaml, https://lists.fedoraproject.org/archives/list/[email protected]/message/KEVRB4MG5UXQ5RLZHSUJXM5GWEBYYS5B, https://lists.fedoraproject.org/archives/list/[email protected]/message/N6P4QULVUE254WI7XF2LWWOGHCYVFXFY, https://lists.fedoraproject.org/archives/list/[email protected]/message/WRO4MPQ6HOXIUZM6RJP6VTCTMV7RD2T3, https://matrix-org.github.io/synapse/latest/admin_api/rooms.html#version-2-new-version, https://security.gentoo.org/glsa/202401-12

    Affected packages

    Package

    Name: matrix-synapse

    Purl: pkg:pypi/matrix-synapse

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -1.94.0

    Affected versions

    0.33.5
    0.33.5.1
    0.33.6
    0.33.6rc1
    0.33.7
    0.33.7rc1
    0.33.7rc2
    0.33.8
    0.33.8rc2
    0.33.9

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    GHSA-5chr-wjw5-3gq4 | CVE-DB