How severe is CVE-2024-52805?

CVE-2024-52805 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-52805 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-52805?

CVE-2024-52805 affects Matrix Synapse. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-52805?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2024-52805 have an EU (EUVD) identifier?

Yes. CVE-2024-52805 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3505.

When was CVE-2024-52805 published?

CVE-2024-52805 was published on 2024-12-03 and last updated on 2026-06-17.

CVE-2024-52805

CVE-2024-52805 is a high-severity vulnerability in Matrix Synapse with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.2
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-3505
Weakness: CWE-770
Affected product: Matrix Synapse
Published: 2024-12-03
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2024-52805?: 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.
How severe is CVE-2024-52805?: CVE-2024-52805 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-52805 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-52805?: CVE-2024-52805 affects Matrix Synapse. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-52805?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-52805 have an EU (EUVD) identifier?: Yes. CVE-2024-52805 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3505.
When was CVE-2024-52805 published?: CVE-2024-52805 was published on 2024-12-03 and last updated on 2026-06-17.

References

Affected products (1)

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

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