CVSS: 7.8EPSS: 0%CPEs: 4EXPL: 0CVE-2021-26930
https://notcve.org/view.php?id=CVE-2021-26930
An issue was discovered in the Linux kernel 3.11 through 5.10.16, as used by Xen. To service requests to the PV backend, the driver maps grant references provided by the frontend. In this process, errors may be encountered. In one case, an error encountered earlier might be discarded by later processing, resulting in the caller assuming successful mapping, and hence subsequent operations trying to access space that wasn't mapped. In another case, internal state would be insufficiently updated, preventing safe recovery from the error. • http://xenbits.xen.org/xsa/advisory-365.html https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=871997bc9e423f05c7da7c9178e62dde5df2a7f8 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 •
CVSS: 5.5EPSS: 0%CPEs: 4EXPL: 0CVE-2021-26931
https://notcve.org/view.php?id=CVE-2021-26931
An issue was discovered in the Linux kernel 2.6.39 through 5.10.16, as used in Xen. Block, net, and SCSI backends consider certain errors a plain bug, deliberately causing a kernel crash. For errors potentially being at least under the influence of guests (such as out of memory conditions), it isn't correct to assume a plain bug. Memory allocations potentially causing such crashes occur only when Linux is running in PV mode, though. This affects drivers/block/xen-blkback/blkback.c and drivers/xen/xen-scsiback.c. • http://xenbits.xen.org/xsa/advisory-362.html https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3194a1746e8aabe86075fd3c5e7cf1f4632d7f16 https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5a264285ed1cd32e26d9de4f3c8c6855e467fd63 https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7c77474b2d22176d2bfb592ec74e0f2cb71352c9 https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html https://lists.debian.org/debian-lts-announce/2021/03/m • CWE-770: Allocation of Resources Without Limits or Throttling •
CVSS: 5.5EPSS: 0%CPEs: 10EXPL: 0CVE-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 •
CVSS: 7.8EPSS: 0%CPEs: 5EXPL: 1CVE-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 •
CVSS: 6.5EPSS: 0%CPEs: 3EXPL: 0CVE-2021-3178
https://notcve.org/view.php?id=CVE-2021-3178
fs/nfsd/nfs3xdr.c in the Linux kernel through 5.10.8, when there is an NFS export of a subdirectory of a filesystem, allows remote attackers to traverse to other parts of the filesystem via READDIRPLUS. NOTE: some parties argue that such a subdirectory export is not intended to prevent this attack; see also the exports(5) no_subtree_check default behavior ** EN DISPUTA ** en el archivo fs/nfsd/nfs3xdr.c en el kernel de Linux versiones hasta 5.10.8, cuando se presenta una exportación NFS de un subdirectorio de un sistema de archivos, permite a atacantes remotos saltar otras partes del sistema de archivos por medio de READDIRPLUS. NOTA: algunas terceros argumentan que tal exportación de subdirectorios no intenta impedir este ataque; véase también el comportamiento predeterminado de no_subtree_check de exports(5) • https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=51b2ee7d006a736a9126e8111d1f24e4fd0afaa6 https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5SGB7TNDVQEOJ7NVTGX56UWHDNQM5TRC https://patchwork.kernel.org/project/linux-nfs/patch/20210111210129.GA11652%40fieldses.org • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') •