Microsoft Security Response Center

**What is the relationship between Mark of the Web and Windows SmartScreen?** When you download a file from the internet, Windows adds the zone identifier or Mark of the Web as an NTFS stream to the file. So, when you run the file, Windows SmartScreen checks if there is a zone identifier Alternate Data Stream (ADS) attached to the file. If the ADS indicates ZoneId=3 which means that the file was downloaded from the internet, the SmartScreen does a reputation check. For more information on SmartScreen, please visit Microsoft Defender SmartScreen overview | Microsoft Learn.

**How could an attacker exploit this vulnerability?** An attacker could send a low-level protocol error containing a fragmented IP packet inside another ICMP packet in its header to the target machine. To trigger the vulnerable code path, an application on the target must be bound to a raw socket.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** An attacker would have to send the victim a malicious URL that the victim would have to execute.

**Is the Preview Pane an attack vector for this vulnerability?** No, the Preview Pane is not an attack vector.

**According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?** Successful exploitation of this vulnerability requires an attacker to gather information specific to the environment of the targeted component.

**According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?** Successful exploitation of this vulnerability requires an attacker to gather information specific to the environment of the targeted component.

**According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?** Successful exploitation of this vulnerability requires an attacker to gather information specific to the environment of the targeted component.

**How could an attacker exploit this vulnerability?** In most situations, an unauthenticated attacker could send a specially crafted packet to a targeted server utilizing the HTTP Protocol Stack (http.sys) to process packets.

**How could an attacker exploit this vulnerability?** To exploit this vulnerability, an unauthenticated attacker would need to send a specially crafted RPC call to an RPC host. This could result in remote code execution on the server side with the same permissions as the RPC service.

**How could an attacker exploit this vulnerability?** An authenticated attacker with normal privileges could send a modified XPS file to a shared printer, which can result in a remote code execution.