CVSS 7.8 · High EPSS 0,29%
Kerentanan Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') pada xen, fedoraproject fedora +2 lainnya. Skor CVSS 3.1 7.8 (High) menurut NVD.
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-table ones), so a malicious guest could exploit the race. For instance, there is a small window where Xen can leak memory if XENMAPSPACE_grant_table is used concurrently. A malicious guest may be able to leak memory, or cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| xen | xen | Semua versi hingga 4.13.0 |
| xen | xen | Versi 4.13.0 rc1 |
| xen | xen | Versi 4.13.0 rc2 |
| fedoraproject | fedora | Versi 30 |
| fedoraproject | fedora | Versi 31 |
| fedoraproject | fedora | Versi 32 |
| debian | debian linux | Versi 10.0 |
| opensuse | leap | Versi 15.1 |