CVE-2023-38691

描述

### Impact A malicious Matrix server can use a foreign user's MXID in an OpenID exchange, allowing a bad actor to impersonate users when using the provisioning API. ### Details The library does not check that the servername part of the `sub` parameter (containing the user's *claimed* MXID) is the same as the servername we are talking to. A malicious actor could spin up a server on any given domain, respond with a `sub` parameter according to the user they want to act as and use the resulting token to perform provisioning requests. ### Workarounds Disable the provisioning API. If the bridge does not use the provisioning API, you are not vulnerable.

如何修補 CVE-2023-38691

要修補 CVE-2023-38691,請將受影響套件升級到下列已修補版本。

• —升級至 8.1.2 或更新版本

CVE-2023-38691 正在被利用嗎?

低 — EPSS 為 0.1%,目前沒有觀察到大規模利用活動。

受影響套件(1)

• >= 4.0.0, < 8.1.2

CVSS 分數

參考連結(4)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2023-38691
• PATCHgithub.com/matrix-org/matrix-appservice-bridge
• WEBgithub.com/matrix-org/matrix-appservice-bridge/commit/4c6723a5e7beda65cdf1ae5dbb882e8beaac8552
• WEBgithub.com/matrix-org/matrix-appservice-bridge/security/advisories/GHSA-vc7j-h8xg-fv5x