Denial of service attack via incorrect parameters in Matrix Synapse

TRUNG BÌNH 6.5CVE-2020-26257 · GHSA-hxmp-pqch-c8mm · PYSEC-2020-236 · Công bố 09/12/2020 · cập nhật 17/06/2026

Tóm tắt nhanh

CVE-2020-26257 là lỗ hổng mức TRUNG BÌNH (CVSS 6.5) ảnh hưởng matrix-synapse, synapse (matrix).
Xác suất bị khai thác trong 30 ngày tới (EPSS): 2.4%, cao hơn 84.0% các lỗ hổng khác.
Cách xử lý: cập nhật lên 1.23.1 hoặc mới hơn.

Gói / sản phẩm	Phiên bản bị ảnh hưởng	Phiên bản đã vá
matrix-synapse PyPI	`< 1.23.1`	`1.23.1`
synapse matrix	`< 1.23.1`	`1.23.1`

Mô tả

Impact

A malicious or poorly-implemented homeserver can inject malformed events into a room by specifying a different room id in the path of a /send_join, /send_leave, /invite or /exchange_third_party_invite request.

This can lead to a denial of service in which future events will not be correctly sent to other servers over federation.

This affects any server which accepts federation requests from untrusted servers.

Patches

Issue is resolved by https://github.com/matrix-org/synapse/pull/8776.

Workarounds

Homeserver administrators could limit access to the federation API to trusted servers (for example via federation_domain_whitelist).

Mô tả của NVD

Matrix is an ecosystem for open federated Instant Messaging and VoIP. Synapse is a reference "homeserver" implementation of Matrix. A malicious or poorly-implemented homeserver can inject malformed events into a room by specifying a different room id in the path of a `/send_join`, `/send_leave`, `/invite` or `/exchange_third_party_invite` request. This can lead to a denial of service in which future events will not be correctly sent to other servers over federation. This affects any server which accepts federation requests from untrusted servers. The Matrix Synapse reference implementation before version 1.23.1 the implementation is vulnerable to this injection attack. Issue is fixed in version 1.23.1. As a workaround homeserver administrators could limit access to the federation API to trusted servers (for example via `federation_domain_whitelist`).