CVE-2021-21394mediumCWE-20

CVE-2021-21394: fallo de gravedad media en matrix-org synapse

Denial of service (via resource exhaustion) due to improper input validation on third-party identifier endpoints

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear synapse+ Monitorear matrix-synapse

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

13Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 5.3epss 1.5%
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 1.28.0 Synapse is missing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk space and memory leading to resource exhaustion. Note that the groups feature is not part of the Matrix specification and the chosen maximum lengths are arbitrary. Not all clients might abide by them. Refer to referenced GitHub security advisory for additional details including workarounds.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Productos afectados
matrix-org · synapse
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