CVE-2020-25639
https://notcve.org/view.php?id=CVE-2020-25639
A NULL pointer dereference flaw was found in the Linux kernel's GPU Nouveau driver functionality in versions prior to 5.12-rc1 in the way the user calls ioctl DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC. This flaw allows a local user to crash the system. Se encontró un fallo de desreferencia del puntero NULL en la funcionalidad del controlador GPU Nouveau del kernel de Linux en versiones anteriores a 5.12-rc1, en la manera en que el usuario llama a ioctl DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC. Este fallo permite que un usuario local bloquee el sistema • https://bugzilla.redhat.com/show_bug.cgi?id=1876995 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HE4CT3NL6OEBRRBUKHIX63GLNVOWCVRW https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SUCBCKRHWP3UD2AVVYQJE7BIJEMCMXW5 • CWE-476: NULL Pointer Dereference •
CVE-2021-20194 – kernel: heap overflow in __cgroup_bpf_run_filter_getsockopt()
https://notcve.org/view.php?id=CVE-2021-20194
There is a vulnerability in the linux kernel versions higher than 5.2 (if kernel compiled with config params CONFIG_BPF_SYSCALL=y , CONFIG_BPF=y , CONFIG_CGROUPS=y , CONFIG_CGROUP_BPF=y , CONFIG_HARDENED_USERCOPY not set, and BPF hook to getsockopt is registered). As result of BPF execution, the local user can trigger bug in __cgroup_bpf_run_filter_getsockopt() function that can lead to heap overflow (because of non-hardened usercopy). The impact of attack could be deny of service or possibly privileges escalation. Se presenta una vulnerabilidad en el kernel de Linux versiones superiores a 5.2 (si el kernel compilado con los parámetros config CONFIG_BPF_SYSCALL=y , CONFIG_BPF=y , CONFIG_CGROUPS=y , CONFIG_CGROUP_BPF=y , CONFIG_HARDENED_USERCOPY no se establece y el hook BPF a getsockopt está registrado). Como resultado de la ejecución de BPF, el usuario local puede desencadenar un error en la función __cgroup_bpf_run_filter_getsockopt() que puede conllevar a un desbordamiento de la pila (debido a una copia de usuario no reforzada). • https://bugzilla.redhat.com/show_bug.cgi?id=1912683 https://security.netapp.com/advisory/ntap-20210326-0003 https://access.redhat.com/security/cve/CVE-2021-20194 • CWE-20: Improper Input Validation CWE-400: Uncontrolled Resource Consumption CWE-787: Out-of-bounds Write •
CVE-2021-20182 – openshift: builder allows read and write of block devices
https://notcve.org/view.php?id=CVE-2021-20182
A privilege escalation flaw was found in openshift4/ose-docker-builder. The build container runs with high privileges using a chrooted environment instead of runc. If an attacker can gain access to this build container, they can potentially utilize the raw devices of the underlying node, such as the network and storage devices, to at least escalate their privileges to that of the cluster admin. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. Se encontró un fallo de escalada de privilegios en openshift4/ose-docker-builder. • https://bugzilla.redhat.com/show_bug.cgi?id=1915110 https://access.redhat.com/security/cve/CVE-2021-20182 • CWE-552: Files or Directories Accessible to External Parties •
CVE-2020-27777 – kernel: powerpc: RTAS calls can be used to compromise kernel integrity
https://notcve.org/view.php?id=CVE-2020-27777
A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel. Se encontró un fallo en la manera en que RTAS manejaba los accesos a la memoria en el espacio de usuario para la comunicación del kernel. En un sistema invitado bloqueado (generalmente debido al arranque seguro) que se ejecuta en la parte superior de los hipervisores PowerVM o KVM (plataforma pseries), un usuario root como local podría usar este fallo para aumentar aún más sus privilegios a los de un kernel en ejecución A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel. • https://bugzilla.redhat.com/show_bug.cgi?id=1900844 https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=bd59380c5ba4147dcbaad3e582b55ccfd120b764 https://www.openwall.com/lists/oss-security/2020/10/09/1 https://www.openwall.com/lists/oss-security/2020/11/23/2 https://access.redhat.com/security/cve/CVE-2020-27777 • CWE-862: Missing Authorization •
CVE-2020-27786 – kernel: use-after-free in kernel midi subsystem
https://notcve.org/view.php?id=CVE-2020-27786
A flaw was found in the Linux kernel’s implementation of MIDI, where an attacker with a local account and the permissions to issue ioctl commands to midi devices could trigger a use-after-free issue. A write to this specific memory while freed and before use causes the flow of execution to change and possibly allow for memory corruption or privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability. Se encontró un fallo en la implementación de MIDI en el kernel de Linux, donde un atacante con una cuenta local y los permisos para emitir comandos ioctl a dispositivos midi podría desencadenar un problema de uso después de la liberación. Una escritura en esta memoria específica mientras está liberada y antes de su uso hace que el flujo de ejecución cambie y posiblemente permita la corrupción de memoria o la escalada de privilegios. • https://github.com/kiks7/CVE-2020-27786-Kernel-Exploit https://github.com/elbiazo/CVE-2020-27786 https://github.com/ii4gsp/CVE-2020-27786 http://www.openwall.com/lists/oss-security/2020/12/03/1 https://bugzilla.redhat.com/show_bug.cgi?id=1900933 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d https://security.netapp.com/advisory/ntap-20210122-0002 https://access.redhat.com/security/cve/CVE-2020-27786 • CWE-416: Use After Free •