CVSS: 4.9EPSS: 0%CPEs: 4EXPL: 0CVE-2021-20317 – kernel: timer tree corruption leads to missing wakeup and system freeze
https://notcve.org/view.php?id=CVE-2021-20317
A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP. Se ha encontrado un fallo en el kernel de Linux. Un árbol de temporizadores corrompido hacía que faltara el despertar de la tarea en la función timerqueue_add en el archivo lib/timerqueue.c. • https://bugzilla.redhat.com/show_bug.cgi?id=2005258 https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=511885d7061eda3eb1faf3f57dcc936ff75863f1 https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html https://www.debian.org/security/2022/dsa-5096 https://access.redhat.com/security/cve/CVE-2021-20317 • CWE-665: Improper Initialization •
CVSS: 7.8EPSS: 0%CPEs: 24EXPL: 1CVE-2021-38300
https://notcve.org/view.php?id=CVE-2021-38300
arch/mips/net/bpf_jit.c in the Linux kernel before 5.4.10 can generate undesirable machine code when transforming unprivileged cBPF programs, allowing execution of arbitrary code within the kernel context. This occurs because conditional branches can exceed the 128 KB limit of the MIPS architecture. arch/mips/net/bpf_jit.c en el kernel de Linux anterior a la versión 5.4.10 puede generar código máquina no deseado al transformar programas cBPF sin privilegios, permitiendo la ejecución de código arbitrario dentro del contexto del kernel. Esto ocurre porque las ramas condicionales pueden superar el límite de 128 KB de la arquitectura MIPS • http://www.openwall.com/lists/oss-security/2021/09/15/5 https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14.10 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=37cb28ec7d3a36a5bace7063a3dba633ab110f8b https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html https://security.netapp.com/advisory/ntap-20211008-0003 https://www.debian.org/security/2022/dsa-5096 •
CVSS: 7.8EPSS: 0%CPEs: 25EXPL: 0CVE-2021-41073
https://notcve.org/view.php?id=CVE-2021-41073
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc/<pid>/maps for exploitation. La función loop_rw_iter en fs/io_uring.c en el kernel de Linux desde la versión 5.10 hasta la versión 5.14.6 permite a los usuarios locales ganar privilegios mediante el uso de IORING_OP_PROVIDE_BUFFERS para desencadenar una liberación de un búfer del kernel, como se ha demostrado utilizando /proc//maps para su explotación • http://www.openwall.com/lists/oss-security/2021/09/18/2 http://www.openwall.com/lists/oss-security/2022/06/04/4 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=16c8d2df7ec0eed31b7d3b61cb13206a7fb930cc https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J7KSMIOQ4377CVTHMWNGNCWHMCRFRP2T https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAP4TXEZ7J4EZQMQW5SIJMWXG7WZT3F7 https://security.netapp.com/advisory/nta • CWE-763: Release of Invalid Pointer or Reference •
CVSS: 8.8EPSS: 0%CPEs: 76EXPL: 1CVE-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 •
CVSS: 8.8EPSS: 0%CPEs: 15EXPL: 1CVE-2021-3653 – kernel: SVM nested virtualization issue in KVM (AVIC support)
https://notcve.org/view.php?id=CVE-2021-3653
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 "int_ctl" field, this issue could allow a malicious L1 to enable AVIC support (Advanced Virtual Interrupt Controller) 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. This flaw affects Linux kernel versions prior to 5.14-rc7. • http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html https://bugzilla.redhat.com/show_bug.cgi?id=1983686 https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html https://www.openwall.com/lists/oss-security/2021/08/16/1 https://access.redhat.com/security/cve/CVE-2021-3653 • CWE-862: Missing Authorization •