Synapse is an open-source Matrix homeserver. In Synapse before 1.120.1, multipart/form-data requests can in certain configurations transiently increase memory consumption beyond expected levels while processing the request, which can be used to amplify denial of service attacks. Synapse 1.120.1 resolves the issue by denying requests with unsupported multipart/form-data content type.

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00121.

Exploitation none

Automatable yes

Technical Impact partial

Affected Vendors & Products

Vendors Products
Element-hq
  • Synapse
Matrix
  • Synapse

Configuration 1 [-]

cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*

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Advisories
Source ID Title
EUVD EUVD EUVD-2024-3505 Synapse is an open-source Matrix homeserver. In Synapse before 1.120.1, multipart/form-data requests can in certain configurations transiently increase memory consumption beyond expected levels while processing the request, which can be used to amplify denial of service attacks. Synapse 1.120.1 resolves the issue by denying requests with unsupported multipart/form-data content type.
Github GHSA Github GHSA GHSA-rfq8-j7rh-8hf2 Synapse allows unsupported content types to lead to memory exhaustion
Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/element-hq/synapse/security/advisories/GHSA-rfq8-j7rh-8hf2 cve-icon cve-icon
https://github.com/twisted/twisted/issues/4688#issuecomment-1167705518 cve-icon cve-icon
https://github.com/twisted/twisted/issues/4688#issuecomment-2385711609 cve-icon cve-icon
History

Tue, 26 Aug 2025 15:15:00 +0000

Type Values Removed Values Added
First Time appeared Matrix
Matrix synapse
CPEs cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*
Vendors & Products Matrix
Matrix synapse
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00123}

 epss

{'score': 0.00101}

Tue, 03 Dec 2024 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Element-hq
Element-hq synapse
CPEs cpe:2.3:a:element-hq:synapse:*:*:*:*:*:*:*:*
Vendors & Products Element-hq
Element-hq synapse
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Tue, 03 Dec 2024 17:15:00 +0000

Type Values Removed Values Added
Description Synapse is an open-source Matrix homeserver. In Synapse before 1.120.1, multipart/form-data requests can in certain configurations transiently increase memory consumption beyond expected levels while processing the request, which can be used to amplify denial of service attacks. Synapse 1.120.1 resolves the issue by denying requests with unsupported multipart/form-data content type.
Title Synapse allows unsupported content types to lead to memory exhaustion
Weaknesses CWE-770
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2024-12-03T19:04:44.446Z

Reserved: 2024-11-15T17:11:13.442Z

Link: CVE-2024-52805

cve-icon Vulnrichment

Updated: 2024-12-03T19:04:38.298Z

cve-icon NVD

Status : Analyzed

Published: 2024-12-03T17:15:12.120

Modified: 2025-08-26T15:06:04.290

Link: CVE-2024-52805

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.