CVE-2020-26891: Cross-site Scripting
(updated )
AuthRestServlet in Matrix Synapse is vulnerable to XSS due to unsafe interpolation of the session GET
parameter. This allows a remote attacker to execute an XSS attack on the domain Synapse is hosted on, by supplying the victim user with a malicious URL to the /_matrix/client/r0/auth/*/fallback/web
or /_matrix/client/unstable/auth/*/fallback/web
Synapse endpoints.
References
Detect and mitigate CVE-2020-26891 with GitLab Dependency Scanning
Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →