An integer overflow vulnerability was found in the virtio-snd device via PCM_INFO requests from the guest. A malicious guest can provide out-of-bounds stream counts, potentially leading to unbounded memory allocation on the host and a denial of service condition.

A flaw was found in QEMU. When reading input audio in the virtio-snd device input callback, the `virtio_snd_pcm_in_cb` function did not check whether the iov could fit the data buffer, potentially leading to a heap out-of-bounds write. This issue exists due to an incomplete fix for CVE-2024-7730.

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] To create and manage guests, domctl operations are used by the control domain, a possible Xenstore domain, or by a domain controlling a particular guest. Some of these operations may not be executed in parallel, so a system-wide lock is used. The way that lock is acquired is, however, not providing any fairness. This is CVE-2026-42489. Furthermore, with XSM/Flask in use, the lock acquire will, for some operations, occur ahead of any permission checking. This is CVE-2026-42490.

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] To create and manage guests, domctl operations are used by the control domain, a possible Xenstore domain, or by a domain controlling a particular guest. Some of these operations may not be executed in parallel, so a system-wide lock is used. The way that lock is acquired is, however, not providing any fairness. This is CVE-2026-42489. Furthermore, with XSM/Flask in use, the lock acquire will, for some operations, occur ahead of any permission checking. This is CVE-2026-42490.

HVM guest I/O port accesses are subject to either emulation or at least translation. Translations are managed by the device model (via XEN_DOMCTL_ioport_mapping), and hence the linked list used may changed at any time. Traversal of those lists (while handling guest I/O port accesses) therefore needs synchronizing with updates, which was missing so far.

Some shadow paging errors paths will switch the page-tables without updating the currently running vCPU reference. This causes a mismatch between the loaded page-tables and the mapcache metadata which can lead to corruption of the mapcache.

A flaw was found in the virtio-crypto device of QEMU. A malicious guest operating system can exploit a missing length limit in the AKCIPHER path, leading to uncontrolled memory allocation. This can result in a denial of service (DoS) on the host system by causing the QEMU process to terminate unexpectedly.