Wei Liu

**Name of the Vulnerable Software and Affected Versions** Linux kernel versions prior to 6.6.37 **Description** In CoCo VMs, it is possible for the untrusted host to cause `set memory encrypted()` or `set memory decrypted()` to fail, resulting in shared memory. Callers need to handle these errors to avoid returning decrypted (shared) memory to the page allocator, which could lead to functional or security issues. The `netvsc` driver could free decrypted/shared pages if `set memory decrypted()` fails. Checking the `decrypted` field in the `gpadl` can decide whether to free the memory. **Recommendations** To resolve the issue, update to Linux kernel version 6.6.37 or later. As a temporary workaround, consider checking the `decrypted` field in the `gpadl` to decide whether to free the memory, and handle errors from `set memory encrypted()` and `set memory decrypted()` to avoid returning decrypted (shared) memory to the page allocator.

**Name of the Vulnerable Software and Affected Versions** Xen versions 4.4.x through 4.9.x **Description** An issue allows ARM guest OS users to cause a denial of service, preventing physical CPU usage, due to lock mishandling when an add-to-physmap error is detected. **Recommendations** For Xen versions 4.4.x through 4.9.x, at the moment, there is no information about a newer version that contains a fix for this issue.

**Name of the Vulnerable Software and Affected Versions** Xen versions 4.6.x and earlier **Description** The issue allows local OS guest administrators to cause a denial of service or gain host OS privileges by manipulating information in guest-controlled areas of xenstore. This can lead to resource consumption or management facility confusion. **Recommendations** For Xen versions 4.6.x and earlier, at the moment, there is no information about a newer version that contains a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** Xen versions prior to 4.7 **Description** The issue allows local guest OS users with access to the driver domain to cause a denial of service by manipulating information in the backend directories in xenstore. This can lead to management tool confusion. **Recommendations** For versions prior to 4.7, update to version 4.7 or later to resolve the issue.

**Name of the Vulnerable Software and Affected Versions** Xen (affected versions not specified) **Description** The issue allows local guest administrators to cause a denial of service, resulting in a "scheduling while atomic" error and host crash, by sending a malformed packet. This occurs when using certain Linux versions that do not allow sleeping in softirq context, causing a mutex to be taken when trying to disable the interface. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.