CVE-2024-52815: synapse Input Validation Flaw — Fix

Description

Synapse is an open-source Matrix homeserver. Synapse versions before 1.120.1 fail to properly validate invites received over federation. This vulnerability allows a malicious server to send a specially crafted invite that disrupts the invited user's /sync functionality. Synapse 1.120.1 rejects such invalid invites received over federation and restores the ability to sync for affected users.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weakness Type (CWE)

CWE-20 Improper Input Validation

Affected Products

Vendor	Product	Versions
matrix	synapse	< 1.120.1

References

Advisories & Patches

https://github.com/element-hq/synapse/security/advisories/GHSA-f3r3-h2mq-hx2h

Frequently Asked Questions

What is CVE-2024-52815? +

Synapse is an open-source Matrix homeserver. Synapse versions before 1.120.1 fail to properly validate invites received over federation. This vulnerability allows a malicious server to send a specially crafted invite that disrupts the invited user's /sync functionality. Synapse 1.120.1 rejects such invalid invites received over federation and restores the ability to sync for affected users. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2024-52815? +

CVE-2024-52815 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-52815? +

CVE-2024-52815 affects products from matrix, specifically: synapse. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-52815? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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