374 results (0.011 seconds)

CVSS: 3.3EPSS: 0%CPEs: 1EXPL: 0

Arm provides multiple helpers to clean & invalidate the cache for a given region. This is, for instance, used when allocating guest memory to ensure any writes (such as the ones during scrubbing) have reached memory before handing over the page to a guest. Unfortunately, the arithmetics in the helpers can overflow and would then result to skip the cache cleaning/invalidation. Therefore there is no guarantee when all the writes will reach the memory. This undefined behavior was meant to be addressed by XSA-437, but the approach was not sufficient. Arm proporciona múltiples ayudas para limpiar e invalidar el caché de una región determinada. Esto se utiliza, por ejemplo, al asignar memoria de invitado para garantizar que cualquier escritura (como las que se realizan durante la limpieza) haya alcanzado la memoria antes de entregar la página a un invitado. • https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JFVKWYQFRUU3CAS53THTUKXEOUDWI42G https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XLL6SQ6IKFYXLYWITYZCRV5IBRK5G35R https://xenbits.xenproject.org/xsa/advisory-447.html • CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer •

CVSS: 5.5EPSS: 0%CPEs: 1EXPL: 0

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] AMD CPUs since ~2014 have extensions to normal x86 debugging functionality. Xen supports guests using these extensions. Unfortunately there are errors in Xen's handling of the guest state, leading to denials of service. 1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of a previous vCPUs debug mask state. 2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT. This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock up the CPU entirely. [Este registro de información de la CNA se relaciona con múltiples CVE; el texto explica qué aspectos/vulnerabilidades corresponden a cada CVE.] Las CPU AMD desde ~2014 tienen extensiones a la funcionalidad de depuración x86 normal. Xen admite invitados que utilizan estas extensiones. Desafortunadamente, hay errores en el manejo del estado invitado por parte de Xen, lo que lleva a denegaciones de servicio. 1) CVE-2023-34327: una vCPU HVM puede terminar funcionando en el contexto de un estado de máscara de depuración de vCPU anterior. 2) CVE-2023-34328: una vCPU PV puede colocar un punto de interrupción sobre la GDT en vivo. • https://xenbits.xenproject.org/xsa/advisory-444.html •

CVSS: 5.5EPSS: 0%CPEs: 1EXPL: 0

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] AMD CPUs since ~2014 have extensions to normal x86 debugging functionality. Xen supports guests using these extensions. Unfortunately there are errors in Xen's handling of the guest state, leading to denials of service. 1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of a previous vCPUs debug mask state. 2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT. This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock up the CPU entirely. [Este registro de información de la CNA se relaciona con múltiples CVE; el texto explica qué aspectos/vulnerabilidades corresponden a cada CVE.] Las CPU AMD desde ~2014 tienen extensiones a la funcionalidad de depuración x86 normal. Xen admite invitados que utilizan estas extensiones. Desafortunadamente, hay errores en el manejo del estado invitado por parte de Xen, lo que lleva a denegaciones de servicio. 1) CVE-2023-34327: una vCPU HVM puede terminar funcionando en el contexto de un estado de máscara de depuración de vCPU anterior. 2) CVE-2023-34328: una vCPU PV puede colocar un punto de interrupción sobre la GDT en vivo. • https://xenbits.xenproject.org/xsa/advisory-444.html •

CVSS: 5.5EPSS: 0%CPEs: 1EXPL: 0

When a transaction is committed, C Xenstored will first check the quota is correct before attempting to commit any nodes. It would be possible that accounting is temporarily negative if a node has been removed outside of the transaction. Unfortunately, some versions of C Xenstored are assuming that the quota cannot be negative and are using assert() to confirm it. This will lead to C Xenstored crash when tools are built without -DNDEBUG (this is the default). Cuando se confirma una transacción, C Xenstored primero verificará que la cuota sea correcta antes de intentar confirmar cualquier nodo. Sería posible que la contabilidad fuera temporalmente negativa si se hubiera eliminado un nodo fuera de la transacción. • https://xenbits.xenproject.org/xsa/advisory-440.html • CWE-476: NULL Pointer Dereference •

CVSS: 7.8EPSS: 0%CPEs: 1EXPL: 0

For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. Since Xen itself needs to be mapped when PV guests run, Xen and shadowed PV guests run directly the respective shadow page tables. For 64-bit PV guests this means running on the shadow of the guest root page table. In the course of dealing with shortage of memory in the shadow pool associated with a domain, shadows of page tables may be torn down. This tearing down may include the shadow root page table that the CPU in question is presently running on. While a precaution exists to supposedly prevent the tearing down of the underlying live page table, the time window covered by that precaution isn't large enough. • https://xenbits.xenproject.org/xsa/advisory-438.html • CWE-273: Improper Check for Dropped Privileges •