CVE-2025-66622

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/matrix-org/matrix-rust-sdk/commit/4ea0418abefab2aa93f8851a4d39c723e703e6b0	Patch
https://github.com/matrix-org/matrix-rust-sdk/pull/5924	Issue Tracking Patch
https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-jj6p-3m75-g2p3	Patch Vendor Advisory
https://rustsec.org/advisories/RUSTSEC-2025-0135.html	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:matrix:matrix-rust-sdk:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-12-09 16:18

Updated : 2026-03-17 20:27

NVD link : CVE-2025-66622

Mitre link : CVE-2025-66622

CVE.ORG link : CVE-2025-66622

JSON object : View

Products Affected

matrix

matrix-rust-sdk

CWE

CWE-755

Improper Handling of Exceptional Conditions

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