#VU76261 Resource exhaustion in Synapse - CVE-2022-41952

Vulnerability identifier: #VU76261

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-41952

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Synapse
Server applications / Conferencing, Collaboration and VoIP solutions

Vendor: Matrix.org

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to application does not properly control consumption of internal resources when generating URL previews for media stream. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Synapse: before 1.53.0

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External links
https://github.com/matrix-org/synapse/security/advisories/GHSA-4822-jvwx-w47h
https://github.com/matrix-org/synapse/pull/11936
https://github.com/matrix-org/synapse/releases/tag/v1.53.0
https://github.com/matrix-org/synapse/releases/tag/v1.52.0
https://github.com/matrix-org/synapse/pull/11784

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.