CVE-2024-37302

published 2024-12-03

CVE-2024-37302: Synapse is an open-source Matrix homeserver. Synapse versions before 1.106 are vulnerable to a disk fill attack, where an unauthenticated adversary can induce…

Priority P3 43 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

Synapse is an open-source Matrix homeserver. 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. 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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
debian	matrix-synapse	< matrix-synapse 1.116.0-1 (forky)	matrix-synapse 1.116.0-1 (forky)
element-hq	synapse	< 1.106	1.106
matrix	synapse	< 1.106.0	1.106.0

CVSS provenance

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

osv 7.5 HIGH

vendor_debian 7.5 HIGH

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CWE-770