Current Status: Engineers are currently updating the mismatched certificate throughout the affected environment. As the updates progress, customers will incrementally regain the ability to sign in via the SSO.
User Experience: Affected users are unable to sign in to Yammer using the Single Sign-On (SSO) tool.
Customer Impact: The impact is specific to users who utilize the Azure identity provider for SSO authentication. Impact appears to be limited at this time.
Preliminary Root Cause: A certificate mismatch between the Yammer and Azure environment is preventing some customers from signing in to the Yammer service.