QID 981372

QID 981372: Python (pip) Security Update for matrix-synapse (GHSA-2hwx-mjrm-v3g8)

Security update has been released for matrix-synapse to fix the vulnerability.

Note: The preceding description block is extracted directly from the security advisory. Using automation, we have attempted to clean and format it as much as possible without introducing additional issues.

A malicious homeserver could redirect requests to their .well-known file to a large file. This can lead to a denial of service attack where homeservers will consume significantly more resources when requesting the .well-known file of a malicious homeserver.

This affects any server which accepts federation requests from untrusted servers.

  • CVSS V3 rated as High - 6.5 severity.
  • CVSS V2 rated as Medium - 4.3 severity.
  • Solution
    Issue is resolved by #8950. A bug not affecting the security aspects of this was fixed in #9108.Workaround:
    The `federation_domain_whitelist` setting can be used to restrict the homeservers communicated with over federation.
    Vendor References

    CVEs related to QID 981372

    Software Advisories
    Advisory ID Software Component Link
    GHSA-2hwx-mjrm-v3g8 matrix-synapse URL Logo github.com/advisories/GHSA-2hwx-mjrm-v3g8

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