CVE-2023-46837 – arm32: The cache may not be properly cleaned/invalidated (take two)
https://notcve.org/view.php?id=CVE-2023-46837
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 •
CVE-2023-34323 – xenstored: A transaction conflict can crash C Xenstored
https://notcve.org/view.php?id=CVE-2023-34323
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 •
CVE-2023-34321 – arm32: The cache may not be properly cleaned/invalidated
https://notcve.org/view.php?id=CVE-2023-34321
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. 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 depuración) haya llegado a la memoria antes de entregar la página a un invitado. • https://xenbits.xenproject.org/xsa/advisory-437.html • CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer •
CVE-2021-28703
https://notcve.org/view.php?id=CVE-2021-28703
grant table v2 status pages may remain accessible after de-allocation (take two) Guest get permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, get de-allocated when a guest switched (back) from v2 to v1. The freeing of such pages requires that the hypervisor know where in the guest these pages were mapped. The hypervisor tracks only one use within guest space, but racing requests from the guest to insert mappings of these pages may result in any of them to become mapped in multiple locations. • https://security.gentoo.org/glsa/202402-07 https://xenbits.xenproject.org/xsa/advisory-387.txt •
CVE-2021-28689
https://notcve.org/view.php?id=CVE-2021-28689
x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virtualization. In AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit guests. With the focus now being on 64-bit systems, and the availability of explicit hardware support for virtualization, fixing speculation issues in ring 1 is not a priority for processor companies. Indirect Branch Restricted Speculation (IBRS) is an architectural x86 extension put together to combat speculative execution sidechannel attacks, including Spectre v2. • https://xenbits.xenproject.org/xsa/advisory-370.txt • CWE-212: Improper Removal of Sensitive Information Before Storage or Transfer •