Authentication bypass by capture-replay in Microsoft Authentication Library (MSAL) for Node.js allows an unauthorized attacker to perform spoofing over a network.
According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability? Successful exploitation requires an attacker to first obtain a valid ID token issued for the victim and the same application, and then replay it through a separate authentication flow. These prerequisites make exploitation more difficult. What action should customers take to address this vulnerability? Customers should update the @azure/msal-node dependency in each affected application to version 5.6.0 or a later compatible version. From the application's project directory, run npm install @azure/msal-node@^5.6.0 --save, then rebuild, test, and redeploy the application using the organization's standard deployment process. See the MSAL Node v5.6.0 release notes and the @azure/msal-node package on npm for additional information. According to the CVSS metrics, successful exploitation of this vulnerability could lead to major loss of confidentiality (C:H), and integrity (I:H), but could lead to no loss of availability (A:N). What does that mean for this vulnerability? Exploiting this vulnerability could allow an attacker to view highly sensitive user information and modify data, but they cannot affect the availability of the service.