Iniciar sesión
Deutsch English Español Polski
Alta

Synapse denial of service through media disk space consumption

  • Publicada: 03.12.2024
  • Actualizado: 11.10.2026 12:19

Impact

Synapse versions before 1.106 are vulnerable to a disk fill attack, where an unauthenticated adversary can induce Synapse to download and cache large amounts of remote media. The default rate limit strategy is insufficient to mitigate this. This can lead to a denial of service, ranging from further media uploads/downloads failing to completely unavailability of the Synapse process, depending on how Synapse was deployed.

Patches

Synapse 1.106 introduces a new "leaky bucket" rate limit on remote media downloads to reduce the amount of data a user can request at a time. This does not fully address the issue, but does limit an unauthenticated user's ability to request large amounts of data to be cached.

Workarounds

Synapse deployments can currently decrease the maximum file size allowed, as well as increase request rate limits. However, this does not as effectively address the issue as a dedicated rate limit on remote media downloads.

Server operators may also wish to consider putting media on a dedicated disk or volume, reducing the impact of a disk fill condition.

References

For more information

If you have any questions or comments about this advisory, please email us at security at element.io.

Software afectado

Haz clic en una tecnología para ver todas sus vulnerabilidades.

PlataformaPaqueteVersiones vulnerablesCorregida en
Python (PyPI) matrix-synapse < 1.106 1.106

Referencias

Puntuación CVSS 7.5/10
Vector CVSS
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Debilidad (CWE)
CWE-770
Plataforma
Python (PyPI)
Paquete
matrix-synapse
Publicada
03.12.2024
Actualizado
11.10.2026 12:19

Fuentes y licencias

OSV / GitHub Advisory Database - PYSEC-2024-286 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-4mhg-xv73-xq2x - CC BY 4.0

Historial de vulnerabilidades: matrix-synapse

Todas las vulnerabilidades publicadas de este paquete (Python (PyPI)), de la más reciente a la más antigua. Muestra si es un fallo aislado o un paquete que hay que vigilar.

Todas (45) en el archivo
Entradas en total
45
Primera → última
03.2019 05.2026
Sin corrección
0
Explotada en ataques
0

Distribución por gravedad

  • Alta 21
  • Media 21
  • Baja 3

Divulgaciones por año

Gravedad:
  1. Synapse CPU starvation (Denial of Service)
    Alta · 5.5 CVE-2026-45078 < 1.152.1 1.152.1
  2. Synapse vulnerable to federation denial of service via malformed events
    Alta · 7.1 CVE-2025-30355 < 1.127.1 1.127.1
  3. Synapse can be forced to thumbnail unexpected file formats, invoking external, potentially untrustworthy decoders
    Alta CVE-2024-53863 < 1.120.1 1.120.1
  4. Synapse allows a a malformed invite to break the invitee's `/sync`
    Alta CVE-2024-52815 < 1.120.1 1.120.1
  5. Synapse allows unsupported content types to lead to memory exhaustion
    Alta CVE-2024-52805 < 1.120.1 1.120.1
  6. Synapse denial of service through media disk space consumption esta entrada
    Alta · 7.5 CVE-2024-37302 < 1.106 1.106
  7. Synapse Denial of service due to incorrect application of event authorization rules during state resolution
    Alta · 6.5 CVE-2022-39374 >= 1.62.0, < 1.68.0rc1 1.68.0rc1
  8. Synapse does not apply enough checks to servers requesting auth events of events in a room
    Alta · 5.0 CVE-2022-39335 < 1.69.0 1.69.0
  9. Denial of service due to incorrect application of event authorization rules
    Alta · 7.5 CVE-2022-31152 < 1.62.0rc1 1.62.0rc1
  10. URL previews of unusual or maliciously-crafted pages can crash Synapse media repositories or Synapse monoliths
    Alta · 6.5 CVE-2022-31052 < 1.61.1 1.61.1
  11. Matrix Synapse DoS
    Alta · 7.5 CVE-2018-10657 < 0.28.1 0.28.1
  12. Matrix Synapse Improper Signature Validation
    Alta · 8.8 CVE-2018-16515 >= 0.33.3, < 0.33.3.1, < 0.33.2.1 0.33.3.1, 0.33.2.1
  13. Matrix Synapse Authorization Error
    Alta · 7.5 CVE-2018-12423 < 0.31.2 0.31.2
  14. Matrix Synapse Security Filtering Flaw
    Alta · 7.5 CVE-2018-12291 < 0.31.1 0.31.1
  15. Path traversal in Matrix Synapse
    Alta · 7.5 CVE-2021-41281 < 1.47.1 1.47.1
  16. Open redirect via transitional IPv6 addresses on dual-stack networks
    Alta · 6.3 CVE-2021-21392 < 1.28.0rc1 1.28.0rc1
  17. Denial of service attack via incorrect parameters in Matrix Synapse
    Alta · 6.5 CVE-2020-26257 < 1.23.1 1.23.1
  18. Denial of service attack due to invalid JSON
    Alta · 7.5 CVE-2020-26890 < 1.20.0 1.20.0
  19. Improper Verification of Cryptographic Signature in matrix-synapse
    Alta · 8.6 CVE-2019-18835 < 1.5.0 1.5.0
  20. matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG
    Alta · 7.5 CVE-2019-11842 < 0.99.3.1 0.99.3.1
  21. Matrix Synapse before 0.34.0.1, when the macaroon_secret_key authentication parameter is not set, uses a predictable value to derive a secret key and other secrets which could allow remote attackers t
    Alta · 7.5 CVE-2019-5885 < 0.34.0.1 0.34.0.1

Identifica las vulnerabilidades de tu aplicación

Con la integración de DockRay y el inventario de software activado, DockRay compara las versiones notificadas de los componentes con las vulnerabilidades conocidas y avisa de las coincidencias confirmadas. La cobertura depende de la tecnología compatible y de los avisos disponibles.

Conectar tu aplicación
Newsletter DockRay

La seguridad de tus aplicaciones en tu correo

Vulnerabilidades importantes, recomendaciones concretas y consejos prácticos para tus aplicaciones. Elige tus tecnologías y sigue lo que importa para tu proyecto.

  • Un resumen diario de nuevas vulnerabilidades, también las críticas.
  • Avisos sobre actualizaciones importantes.
  • Consejos prácticos sobre seguridad y monitorización de aplicaciones.

Déjalo vacío para recibir avisos de todas las tecnologías.

Política de privacidad

Suscripción gratuita. Date de baja con un clic en cualquier correo.