CVE-2021-21274
Vulnerability from cvelistv5
Published
2021-02-26 17:25
Modified
2024-08-03 18:09
Severity ?
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Summary
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-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. Issue is resolved in version 1.25.0. As a workaround the `federation_domain_whitelist` setting can be used to restrict the homeservers communicated with over federation.
References
security-advisories@github.comhttps://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6Patch, Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/pull/8950Patch, Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/releases/tag/v1.25.0Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8Patch, Third Party Advisory
security-advisories@github.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/commit/ff5c4da1289cb5e097902b3e55b771be342c29d6Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/pull/8950Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/releases/tag/v1.25.0Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/security/advisories/GHSA-2hwx-mjrm-v3g8Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/
Impacted products
Vendor Product Version
Show details on NVD website

To clipboard 

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