CVE-2021-26932
https://notcve.org/view.php?id=CVE-2021-26932
An issue was discovered in the Linux kernel 3.2 through 5.10.16, as used by Xen. Grant mapping operations often occur in batch hypercalls, where a number of operations are done in a single hypercall, the success or failure of each one is reported to the backend driver, and the backend driver then loops over the results, performing follow-up actions based on the success or failure of each operation. Unfortunately, when running in PV mode, the Linux backend drivers mishandle this: Some errors are ignored, effectively implying their success from the success of related batch elements. In other cases, errors resulting from one batch element lead to further batch elements not being inspected, and hence successful ones to not be possible to properly unmap upon error recovery. Only systems with Linux backends running in PV mode are vulnerable. • http://xenbits.xen.org/xsa/advisory-361.html https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ebee0eab08594b2bd5db716288a4f1ae5936e9bc https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2XQR52ICKRK3GC4HDWLMWF2U55YGAR63 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GWQWPWYZRX •
CVE-2021-3348 – kernel: Use-after-free in ndb_queue_rq() in drivers/block/nbd.c
https://notcve.org/view.php?id=CVE-2021-3348
nbd_add_socket in drivers/block/nbd.c in the Linux kernel through 5.10.12 has an ndb_queue_rq use-after-free that could be triggered by local attackers (with access to the nbd device) via an I/O request at a certain point during device setup, aka CID-b98e762e3d71. En la función nbd_add_socket en el archivo drivers/block/nbd.c en el kernel de Linux versiones hasta 5.10.12, presenta un uso de la memoria previamente liberada de ndb_queue_rq que podría ser desencadenado por atacantes locales (con acceso al dispositivo nbd) por medio de una petición de E/S en un punto determinado durante la configuración del dispositivo, también se conoce como CID-b98e762e3d71 A use after free flaw in the Linux kernel network block device (NBD) subsystem was found in the way user calls an ioctl NBD_SET_SOCK at a certain point during device setup. • http://www.openwall.com/lists/oss-security/2021/02/01/1 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b98e762e3d71e893b221f871825dc64694cfb258 https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html https://www.openwall.com/lists/oss-security/2021/01/28/3 https://access.redhat.com/security/cve/CVE-2021-3348 https://bugzilla.redhat.com/show_bug.cgi?id=1921958 • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') CWE-416: Use After Free •
CVE-2021-3347 – kernel: Use after free via PI futex state
https://notcve.org/view.php?id=CVE-2021-3347
An issue was discovered in the Linux kernel through 5.10.11. PI futexes have a kernel stack use-after-free during fault handling, allowing local users to execute code in the kernel, aka CID-34b1a1ce1458. Se detectó un problema en el kernel de Linux versiones hasta 5.10.11. Los futexes de PI presentan un uso de la memoria previamente liberada de la pila del kernel durante el manejo de fallos, permitiendo a usuarios locales ejecutar código en el kernel, también se conoce como CID-34b1a1ce1458 A flaw was found in the Linux kernel. A use-after-free memory flaw in the Fast Userspace Mutexes functionality allowing a local user to crash the system or escalate their privileges on the system. • http://www.openwall.com/lists/oss-security/2021/01/29/4 http://www.openwall.com/lists/oss-security/2021/01/29/5 http://www.openwall.com/lists/oss-security/2021/02/01/4 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=04b79c55201f02ffd675e1231d731365e335c307 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=12bb3f7f1b03d5913b3f9d4236a488aa7774dfe9 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/ • CWE-416: Use After Free •
CVE-2020-25669
https://notcve.org/view.php?id=CVE-2020-25669
A vulnerability was found in the Linux Kernel where the function sunkbd_reinit having been scheduled by sunkbd_interrupt before sunkbd being freed. Though the dangling pointer is set to NULL in sunkbd_disconnect, there is still an alias in sunkbd_reinit causing Use After Free. Se encontró una vulnerabilidad en el Kernel de Linux donde la función sunkbd_reinit habiendo sido programada por la función sunkbd_interrupt antes de que sunkbd fuera liberada. Aunque el puntero colgante está establecido en NULL en la función sunkbd_disconnect, todavía se presenta un alias en sunkbd_reinit causando un Uso de la Memoria Previamente Liberada • http://www.openwall.com/lists/oss-security/2020/11/05/2 http://www.openwall.com/lists/oss-security/2020/11/20/5 https://github.com/torvalds/linux/commit/77e70d351db7de07a46ac49b87a6c3c7a60fca7e https://lists.debian.org/debian-lts-announce/2020/12/msg00015.html https://lists.debian.org/debian-lts-announce/2020/12/msg00027.html https://security.netapp.com/advisory/ntap-20210702-0006 https://www.openwall.com/lists/oss-security/2020/11/05/2%2C https://www.openwall.com/lists/oss- • CWE-416: Use After Free •
CVE-2020-35513 – kernel: Nfsd failure to clear umask after processing an open or create
https://notcve.org/view.php?id=CVE-2020-35513
A flaw incorrect umask during file or directory modification in the Linux kernel NFS (network file system) functionality was found in the way user create and delete object using NFSv4.2 or newer if both simultaneously accessing the NFS by the other process that is not using new NFSv4.2. A user with access to the NFS could use this flaw to starve the resources causing denial of service. Se encontró un fallo sin máscara incorrecto durante la modificación de archivos o directorios en la funcionalidad Linux kernel NFS (sistema de archivo de red) en la manera en que el usuario crea y elimina objetos usando NFSv4.2 o más reciente si ambos acceden simultáneamente al NFS por el otro proceso que no está usando el nuevo NFSv4.2. Un usuario con acceso al NFS podría usar este fallo para privar de recursos causando una denegación de servicio • https://bugzilla.redhat.com/show_bug.cgi?id=1911309 https://patchwork.kernel.org/project/linux-nfs/patch/20180403203916.GH20297%40fieldses.org https://access.redhat.com/security/cve/CVE-2020-35513 • CWE-271: Privilege Dropping / Lowering Errors •