CVE-2021-3656 – kernel: SVM nested virtualization issue in KVM (VMLOAD/VMSAVE)
https://notcve.org/view.php?id=CVE-2021-3656
A flaw was found in the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "virt_ext" field, this issue could allow a malicious L1 to disable both VMLOAD/VMSAVE intercepts and VLS (Virtual VMLOAD/VMSAVE) for the L2 guest. As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape. Se ha encontrado un fallo en el código AMD de KVM para soportar la virtualización anidada SVM. • https://github.com/rami08448/CVE-2021-3656-Demo https://bugzilla.redhat.com/show_bug.cgi?id=1983988 https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc https://www.openwall.com/lists/oss-security/2021/08/16/1 https://access.redhat.com/security/cve/CVE-2021-3656 • CWE-862: Missing Authorization •
CVE-2019-14821 – Kernel: KVM: OOB memory access via mmio ring buffer
https://notcve.org/view.php?id=CVE-2019-14821
An out-of-bounds access issue was found in the Linux kernel, all versions through 5.3, in the way Linux kernel's KVM hypervisor implements the Coalesced MMIO write operation. It operates on an MMIO ring buffer 'struct kvm_coalesced_mmio' object, wherein write indices 'ring->first' and 'ring->last' value could be supplied by a host user-space process. An unprivileged host user or process with access to '/dev/kvm' device could use this flaw to crash the host kernel, resulting in a denial of service or potentially escalating privileges on the system. Se encontró un problema de acceso fuera de límites en el kernel de Linux, todas las versiones hasta 5.3, en la manera en que el hipervisor KVM del kernel de Linux implementa la operación de escritura MMIO Coalesced. Opera en un objeto MMIO ring buffer "struct kvm_coalesced_mmio", en donde los índices de escritura "ring-)first" y "ring-)last" podrían ser suministrados por un proceso de espacio de usuario del host. • http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00036.html http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00037.html http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html http://packetstormsecurity.com/files/155212/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html http://www.openwall.com/lists/oss-security/2019/09/20/1 https://access.redhat.com/errata/RHSA-2019:3309 https://access.redhat.com/errata/RHSA-2019:3517 • CWE-787: Out-of-bounds Write •
CVE-2019-14835 – kernel: vhost-net: guest to host kernel escape during migration
https://notcve.org/view.php?id=CVE-2019-14835
A buffer overflow flaw was found, in versions from 2.6.34 to 5.2.x, in the way Linux kernel's vhost functionality that translates virtqueue buffers to IOVs, logged the buffer descriptors during migration. A privileged guest user able to pass descriptors with invalid length to the host when migration is underway, could use this flaw to increase their privileges on the host. Se encontró un fallo de desbordamiento de búfer, en las versiones desde 2.6.34 hasta 5.2.x, en la manera en que la funcionalidad vhost del kernel de Linux que traduce los búferes virtueue en IOV, registraba los descriptores del búfer durante una migración. Un usuario invitado privilegiado capaz de pasar descriptores con una longitud no válida hacia el host cuando la migración está en marcha, podría usar este fallo para aumentar sus privilegios sobre el host. A buffer overflow flaw was found in the way Linux kernel's vhost functionality that translates virtqueue buffers to IOVs, logged the buffer descriptors during migration. • http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00064.html http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00066.html http://packetstormsecurity.com/files/154572/Kernel-Live-Patch-Security-Notice-LSN-0056-1.html http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html http://packetstormsecurity.com/files/155212/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20200115-01- • CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') •
CVE-2019-1125 – Windows Kernel Information Disclosure Vulnerability
https://notcve.org/view.php?id=CVE-2019-1125
An information disclosure vulnerability exists when certain central processing units (CPU) speculatively access memory. An attacker who successfully exploited the vulnerability could read privileged data across trust boundaries. To exploit this vulnerability, an attacker would have to log on to an affected system and run a specially crafted application. The vulnerability would not allow an attacker to elevate user rights directly, but it could be used to obtain information that could be used to try to compromise the affected system further. On January 3, 2018, Microsoft released an advisory and security updates related to a newly-discovered class of hardware vulnerabilities (known as Spectre) involving speculative execution side channels that affect AMD, ARM, and Intel CPUs to varying degrees. This vulnerability, released on August 6, 2019, is a variant of the Spectre Variant 1 speculative execution side channel vulnerability and has been assigned CVE-2019-1125. Microsoft released a security update on July 9, 2019 that addresses the vulnerability through a software change that mitigates how the CPU speculatively accesses memory. Note that this vulnerability does not require a microcode update from your device OEM. • https://www.exploit-db.com/exploits/48071 http://packetstormsecurity.com/files/156337/SWAPGS-Attack-Proof-Of-Concept.html http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20200408-01-swapgs-en https://access.redhat.com/errata/RHBA-2019:2824 https://access.redhat.com/errata/RHBA-2019:3248 https://access.redhat.com/errata/RHSA-2019:2600 https://access.redhat.com/errata/RHSA-2019:2609 https://access.redhat.com/errata/RHSA-2019:2695 https://access.redhat.com/errata/RHS • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor •
CVE-2019-10126 – kernel: Heap overflow in mwifiex_uap_parse_tail_ies function in drivers/net/wireless/marvell/mwifiex/ie.c
https://notcve.org/view.php?id=CVE-2019-10126
A flaw was found in the Linux kernel. A heap based buffer overflow in mwifiex_uap_parse_tail_ies function in drivers/net/wireless/marvell/mwifiex/ie.c might lead to memory corruption and possibly other consequences. Se encontró un defecto en el kernel de Linux. Un desbordamiento de búfer en la región heap de la memoria en la función mwifiex_uap_parse_tail_ies en el archivo drivers/net/wireless/marvell/mwifiex/ie.c, podría provocar corrupción de la memoria y posiblemente otras consecuencias. A flaw was found in the mwifiex implementation in the Linux kernel. • http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00014.html http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00025.html http://packetstormsecurity.com/files/153702/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html http://packetstormsecurity.com/files/154245/Kernel-Live-Patch-Security-Notice-LSN-0054-1.html http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html http://www.securityfocus.com/bid/108817 https://access.redhat.com/errat • CWE-122: Heap-based Buffer Overflow CWE-787: Out-of-bounds Write •