CVE-2023-38691
Severity CVSS v4.0:
Pending analysis
Type:
CWE-287
Authentication Issues
Publication date:
04/08/2023
Last modified:
11/08/2023
Description
matrix-appservice-bridge provides an API for setting up bridges. Starting in version 4.0.0 and prior to versions 8.1.2 and 9.0.1, 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. The library does not check that the servername part of the `sub` parameter (containing the user's *claimed* MXID) is the 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. Versions 8.1.2 and 9.0.1 contain a patch. As a workaround, disable the provisioning API.
Impact
Base Score 3.x
6.50
Severity 3.x
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:matrix:matrix-appservice-bridge:*:*:*:*:*:node.js:*:* | 4.0.0 (including) | 8.1.2 (excluding) |
| cpe:2.3:a:matrix:matrix-appservice-bridge:9.0.0:*:*:*:*:node.js:*:* |
To consult the complete list of CPE names with products and versions, see this page