#Security Vulnerability

**What privileges could an attacker gain?** An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

**How could an attacker exploit this vulnerability?** This vulnerability could be exploited over the network by making an unauthenticated, specially crafted call to a Network File System (NFS) service to trigger a Remote Code Execution (RCE).

**What type of information could be disclosed by this vulnerability?** The type of information that could be disclosed if an attacker successfully exploited this vulnerability is uninitialized memory.

**In what scenarios is my computer vulnerable?** For Windows 11 and Windows 10 the FAX service is not installed by default. For the vulnerability to be exploitable, the Windows Fax and Scan feature needs to be enabled, and the Fax service needs to be running. Systems that do not have the Fax service running are not vulnerable. **How can I verify whether the Fax service is running?** 1. Hold the **Windows key** and press **R** on your keyboard. This will open the Run dialog. 2. Type _services.msc_ and press **Enter** to open the Services window. 3. Scroll through the list and locate the **Fax** service. * If the Fax service is not listed, Windows Fax and Scan is not enabled and the system is not vulnerable. * If the Fax service is listed but the status is not _Running_, then the system is not vulnerable at the time, but could be targeted if the service was started. The update should be installed as soon as possible or the Fax service should be removed if not needed.

**According to the CVSS metric, successful exploitation could lead to scope change (S:C). What does this mean for this vulnerability?** A locally authenticated attacker could send specially crafted data to the local CSRSS service to elevate their privileges from AppContainer to SYSTEM. Because the AppContainer environment is considered a defensible security boundary, any process that is able to bypass the boundary is considered a change in Scope. The attacker could then execute code or access resources at a higher integrity level than that of the AppContainer execution environment.

**In what scenarios is my computer vulnerable?** For Windows 11 and Windows 10 the FAX service is not installed by default. For the vulnerability to be exploitable, the Windows Fax and Scan feature needs to be enabled, and the Fax service needs to be running. Systems that do not have the Fax service running are not vulnerable. **How can I verify whether the Fax service is running?** 1. Hold the **Windows key** and press **R** on your keyboard. This will open the Run dialog. 2. Type _services.msc_ and press **Enter** to open the Services window. 3. Scroll through the list and locate the **Fax** service. * If the Fax service is not listed, Windows Fax and Scan is not enabled and the system is not vulnerable. * If the Fax service is listed but the status is not _Running_, then the system is not vulnerable at the time, but could be targeted if the service was started. The update should be installed as soon as possible or the Fax service should be removed if not needed.

**In what scenarios can the security feature be bypassed?** On machines with slow or older USB controller hardware, the Group policy might have (silently) failed to apply. On such machines, the attacker can trivially exploit this enforcement failure by attaching a USB storage device to the affected machine.

**What privileges could be gained by an attacker who successfully exploited the vulnerability?** An attacker would only be able to delete targeted files on a system. They would not gain privileges to view or modify file contents.

**What privileges could be gained by an attacker who successfully exploited the vulnerability?** An attacker would only be able to delete targeted files on a system. They would not gain privileges to view or modify file contents.

**According to the CVSS metric, Confidentiality is None (C:N), Integrity is High (I:H), and Availability is High (A:H). How could an attacker impact the Windows Media player?** An attacker who successfully exploited this vulnerability could affect the integrity and availability because they could delete privileged registry keys. Confidentiality is not affected by a successful attack, however, because the attacker cannot read or modify the information.