CVE-2021-41281
Path traversal in Matrix Synapse
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
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.
Synapse es un paquete para servidores domésticos Matrix escrito en Python 3/Twisted. En versiones anteriores a 1.47.1, las instancias de Synapse con el repositorio de medios habilitado pueden ser engañadas para descargar un archivo de un servidor remoto en un directorio arbitrario. No es requerida autenticación para el endpoint afectado. Los dos últimos directorios y el nombre del archivo de la ruta son elegidos al azar por Synapse y no pueden ser controlados por un atacante, lo que limita el impacto. Los servidores domésticos con el repositorio de medios deshabilitado no están afectados. Los servidores domésticos con una lista blanca de la federación tampoco están afectados, ya que Synapse comprobará el nombre de host remoto, incluyendo el final "../", con la lista blanca. Los administradores de servidores deben actualizar a la versión 1.47.1 o posterior. Los administradores de servidores que usen un proxy inverso podrían, a costa de perder la funcionalidad de los medios de comunicación, bloquear ciertos endpoints como solución. Como alternativa, los despliegues sin contenedores pueden adaptarse para usar la configuración systemd endurecida
CVSS Scores
SSVC
- Decision:-
Timeline
- 2021-09-15 CVE Reserved
- 2021-11-23 CVE Published
- 2024-08-04 CVE Updated
- 2024-08-08 EPSS Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CAPEC
References (5)
| URL | Tag | Source |
|---|---|---|
| https://github.com/matrix-org/synapse/releases/tag/v1.47.1 | Release Notes | |
| https://github.com/matrix-org/synapse/security/advisories/GHSA-3hfw-x7gx-437c | Mitigation |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|---|---|
| https://github.com/matrix-org/synapse/commit/91f2bd090 | 2023-11-07 |
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Matrix Search vendor "Matrix" | Synapse Search vendor "Matrix" for product "Synapse" | < 1.47.1 Search vendor "Matrix" for product "Synapse" and version " < 1.47.1" | - |
Affected
| ||||||
| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 34 Search vendor "Fedoraproject" for product "Fedora" and version "34" | - |
Affected
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| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 35 Search vendor "Fedoraproject" for product "Fedora" and version "35" | - |
Affected
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