matrix-sdk-base is the base component to build a Matrix client library. Versions 0.14.1 and prior are unable to handle responses that include custom m.room.join_rules values due to a serialization bug. This can be exploited to cause a denial-of-service condition, if a user is invited to a room with non-standard join rules, the crate's sync process will stall, preventing further processing for all rooms. This is fixed in version 0.16.0.
History

Tue, 17 Mar 2026 20:30:00 +0000

Type Values Removed Values Added
First Time appeared Matrix
Matrix matrix-rust-sdk
CPEs cpe:2.3:a:matrix:matrix-rust-sdk:*:*:*:*:*:*:*:*
Vendors & Products Matrix
Matrix matrix-rust-sdk
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'}


Tue, 09 Dec 2025 17:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

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


Tue, 09 Dec 2025 10:15:00 +0000

Type Values Removed Values Added
First Time appeared Matrix-org
Matrix-org matrix-rust-sdk
Vendors & Products Matrix-org
Matrix-org matrix-rust-sdk

Tue, 09 Dec 2025 02:30:00 +0000

Type Values Removed Values Added
Description matrix-sdk-base is the base component to build a Matrix client library. Versions 0.14.1 and prior are unable to handle responses that include custom m.room.join_rules values due to a serialization bug. This can be exploited to cause a denial-of-service condition, if a user is invited to a room with non-standard join rules, the crate's sync process will stall, preventing further processing for all rooms. This is fixed in version 0.16.0.
Title matrix-sdk-base is vulnerable to DoS via custom m.room.join_rules event values
Weaknesses CWE-755
References
Metrics cvssV4_0

{'score': 1.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2025-12-09T16:02:47.455Z

Reserved: 2025-12-05T15:18:02.787Z

Link: CVE-2025-66622

cve-icon Vulnrichment

Updated: 2025-12-09T14:16:14.144Z

cve-icon NVD

Status : Analyzed

Published: 2025-12-09T16:18:21.747

Modified: 2026-03-17T20:27:31.650

Link: CVE-2025-66622

cve-icon Redhat

No data.