CVE-2021-41281
Vulnerability from cvelistv5
Published
2021-11-23 19:15
Modified
2024-08-04 03:08
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Summary
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 required for the affected endpoint. The last 2 directories and file name of the path are chosen randomly by Synapse and cannot be controlled by an attacker, which limits the impact. Homeservers with the media repository disabled are unaffected. Homeservers with a federation whitelist are also unaffected, since Synapse will check the remote hostname, including the trailing `../`s, against the whitelist. Server administrators should upgrade to 1.47.1 or later. Server administrators using a reverse proxy could, at the expense of losing media functionality, may block the certain endpoints as a workaround. Alternatively, non-containerized deployments can be adapted to use the hardened systemd config.
References
security-advisories@github.comhttps://github.com/matrix-org/synapse/commit/91f2bd090Patch, Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/releases/tag/v1.47.1Release Notes, Third Party Advisory
security-advisories@github.comhttps://github.com/matrix-org/synapse/security/advisories/GHSA-3hfw-x7gx-437cMitigation, Third Party Advisory
security-advisories@github.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/
security-advisories@github.comhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/commit/91f2bd090Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/releases/tag/v1.47.1Release Notes, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/matrix-org/synapse/security/advisories/GHSA-3hfw-x7gx-437cMitigation, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/
Impacted products
Vendor Product Version
Show details on NVD website

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