CVE-2021-21273

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 IP addresses when calculating the key validity for third-party invite events and sending push notifications. This could cause Synapse to make requests to internal infrastructure. The type of request was not controlled by the user, although limited modification of request bodies was possible. For the most thorough protection server administrators should remove the deprecated `federation_ip_range_blacklist` from their settings after upgrading to Synapse v1.25.0 which will result in Synapse using the improved default IP address restrictions. See the new `ip_range_blacklist` and `ip_range_whitelist` settings if more specific control is necessary.

Link	Resource
https://github.com/matrix-org/synapse/releases/tag/v1.25.0	Third Party Advisory
https://github.com/matrix-org/synapse/commit/30fba6210834a4ecd91badf0c8f3eb278b72e746	Patch Third Party Advisory
https://github.com/matrix-org/synapse/security/advisories/GHSA-v936-j8gp-9q3p	Patch Third Party Advisory
https://github.com/matrix-org/synapse/pull/8821	Patch Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/	Mailing List Third Party Advisory

Configuration 1

cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:* cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

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Published : 2021-02-26 06:15

Updated : 2021-11-23 10:27

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NVD link : CVE-2021-21273

Mitre link : CVE-2021-21273

No products.

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')