SSRF in Sydent due to missing validation of hostnames

中 6.5CVE-2021-29431 · GHSA-9jhm-8m8c-c3f4 · PYSEC-2021-22 · 15/04/2021 公開 · 17/06/2026 更新

要点

CVE-2021-29431 は matrix-sydent, sydent (matrix) に影響する深刻度「中」 (CVSS 6.5) の脆弱性です。
今後30日間に悪用される確率（EPSS）：1.2%（全脆弱性の 68.0% より高い）。
対処：2.3.0 以降に更新してください。

パッケージ	影響を受けるバージョン	修正済みバージョン
matrix-sydent PyPI	`< 2.3.0`	`2.3.0`
sydent matrix	`< 2.3.0`	`2.3.0`

概要

Impact

Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting.

It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perform an internal port enumeration.

Patches

Fixed in 9e57334, 8936925, 3d531ed, 0f00412

Workarounds

A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.

For more information

If you have any questions or comments about this advisory, email us at [email protected].

NVD の説明

Sydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perform an internal port enumeration. This issue has been addressed in in 9e57334, 8936925, 3d531ed, 0f00412. A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.