CVE-2023-38691
CVSS 3.1 Score 6.5 of 10 (medium)
Details
Summary
CVE-2023-38691 is a vulnerability in the matrix-appservice-bridge library, affecting versions 4.0.0 to 8.1.2 and 9.0.1. It allows a malicious Matrix server to impersonate users when using the provisioning API by using a foreign user's MXID in an OpenID exchange. The library does not properly check the servername part of the 'sub' parameter, allowing a bad actor to spin up a server on any domain and respond with a 'sub' parameter according to the targeted user they want to act as. The resulting token can then be used for unauthorized provisioning requests. Versions 8.1.2 and 9.0.1 have been patched, but as a workaround, it is recommended to disable the provisioning API altogether. This vulnerability has a base severity rating of MEDIUM, with LOW privileges required and HIGH confidentiality impact, making it potentially dangerous for organizations using affected products.
Prevent cyber attacks with Recorded Future by prioritizing and patching critical vulnerabilities being exploited by threat actors targeting your industry. Book your demo to learn more.
Advisories, Assessments, and Mitigations
Prioritize, Pinpoint, and Act to Prevent Vulnerability Exploits with Recorded Future
- Gain complete coverage of your cyber, third party, and physical attack surface
- Proactively mitigate threats before they turn into costly attacks
- Make fast, effective, data-driven decisions