A vulnerability was discovered in the github.com/russellhaering/goxmldsig library which is used by Teleport to validate the signatures of XML files used to configure SAML 2.0 connectors. With a carefully crafted XML file, an attacker can completely bypass XML signature validation and pass off an altered file as a signed one.
The goxmldsig library has been updated upstream and Teleport 4.3.7 includes the fix. Any Enterprise SSO users using Okta, Active Directory, OneLogin or custom SAML connectors should upgrade their auth servers to version 4.3.7 and restart Teleport.
If you are unable to upgrade immediately, we suggest deleting SAML connectors for all clusters until the updates can be applied.
Download one of the following releases to mitigate the issue:
Teleport Enterprise 4.3.7
Teleport Enterprise 4.2.12
Teleport Enterprise 4.1.11
All current and previous releases of Enterprise can be downloaded from https://dashboard.gravitational.com.