Vulnerability identifier: #VU23098

Vulnerability risk: Medium

CVSSv3.1: 4.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: N/A

CWE-ID: CWE-287

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 bypass authentication process.

The vulnerability exists due to the application does not remove local threepids upon user deactivation and allows access for deactivated accounts.The problem resides within the "/synapse/storage/data_stores/main/registration.py" and "/synapse/handlers/deactivate_account.py" scripts.

A remote attacker can bypass authentication and gain unauthorized access to the application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Synapse: 1.5.0 - 1.6.0

---

External links
http://github.com/matrix-org/synapse/releases/tag/v1.6.1

---

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.