CVE-2020-11884 – Kernel: s390: page table upgrade in secondary address mode may lead to privilege escalation
https://notcve.org/view.php?id=CVE-2020-11884
In the Linux kernel 4.19 through 5.6.7 on the s390 platform, code execution may occur because of a race condition, as demonstrated by code in enable_sacf_uaccess in arch/s390/lib/uaccess.c that fails to protect against a concurrent page table upgrade, aka CID-3f777e19d171. A crash could also occur. En el kernel de Linux versión 4.9 hasta la versión 5.6.7, en la plataforma s390, una ejecución de código puede presentarse debido a una condición de carrera, como es demostrado por el código en la función enable_sacf_uaccess en el archivo arch/s390/lib/uaccess.c que presenta un fallo al proteger contra una actualización concurrente de la tabla de página, también se conoce como CID-3f777e19d171. Tambíen podría ocurrir un bloqueo A flaw was found in the Linux kernel on s390 architecture. The issue occurs on multiprocessing systems when one s390 CPU is in Secondary Address Mode and another CPU does a kernel page table upgrade. • https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=215d1f3928713d6eaec67244bcda72105b898000 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3f777e19d171670ab558a6d5e6b1ac7f9b6c574f https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3TZBP2HINNAX7HKHCOUMIFVQPV6GWMCZ https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AQUVKC3IPUC5B374VVAZV4J5P3GAUGSW https://lists.fedoraproject.org/archives/list/package-announce%4 • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') CWE-1251: Mirrored Regions with Different Values •
CVE-2020-11868 – ntp: DoS on client ntpd using server mode packet
https://notcve.org/view.php?id=CVE-2020-11868
ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows an off-path attacker to block unauthenticated synchronization via a server mode packet with a spoofed source IP address, because transmissions are rescheduled even when a packet lacks a valid origin timestamp. ntpd en ntp versiones anteriores a 4.2.8p14 y versiones 4.3.x anteriores a 4.3.100, permite a un atacante fuera de ruta bloquear una sincronización no autenticada por medio de un paquete en modo server con una dirección IP de origen falsificado, porque las transmisiones son reprogramados aun cuando un paquete carece de una marca de tiempo de origen valido. A flaw was found in the Network Time Protocol (NTP), where a security issue exists that allows an off-path attacker to prevent the Network Time Protocol daemon (ntpd) from synchronizing with NTP servers not using authentication. A server mode packet with a spoofed source address sent to the client ntpd causes the next transmission to be rescheduled, even if the packet does not have a valid origin timestamp. If the packet is sent to the client frequently enough, it stops polling the server and is unable to synchronize with it. • http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00005.html http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00044.html http://support.ntp.org/bin/view/Main/NtpBug3592 https://bugzilla.redhat.com/show_bug.cgi?id=1716665 https://lists.debian.org/debian-lts-announce/2020/05/msg00004.html https://security.gentoo.org/glsa/202007-12 https://security.netapp.com/advisory/ntap-20200424-0002 https://www.oracle.com//security-alerts/cpujul2021.html https://access • CWE-346: Origin Validation Error CWE-400: Uncontrolled Resource Consumption •
CVE-2019-20636 – kernel: out-of-bounds write via crafted keycode table
https://notcve.org/view.php?id=CVE-2019-20636
In the Linux kernel before 5.4.12, drivers/input/input.c has out-of-bounds writes via a crafted keycode table, as demonstrated by input_set_keycode, aka CID-cb222aed03d7. En el kernel de Linux versiones anteriores a 5.4.12, el archivo drivers/input/input.c presenta escrituras fuera de límites por medio de una tabla de códigos clave diseñada, como es demostrado en la función input_set_keycode, también se conoce como CID-cb222aed03d7. An out-of-bounds write flaw was found in the Linux kernel. A crafted keycode table could be used by drivers/input/input.c to perform the out-of-bounds write. A local user with root access can insert garbage to this keycode table that can lead to out-of-bounds memory access. • https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.12 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cb222aed03d798fc074be55e59d9a112338ee784 https://github.com/torvalds/linux/commit/cb222aed03d798fc074be55e59d9a112338ee784 https://lists.debian.org/debian-lts-announce/2020/06/msg00011.html https://lists.debian.org/debian-lts-announce/2020/06/msg00013.html https://security.netapp.com/advisory/ntap-20200430-0004 https://access.redhat.com/security/cve/CVE-2019-20 • CWE-787: Out-of-bounds Write •
CVE-2020-8835 – Linux kernel bpf verifier vulnerability
https://notcve.org/view.php?id=CVE-2020-8835
In the Linux kernel 5.5.0 and newer, the bpf verifier (kernel/bpf/verifier.c) did not properly restrict the register bounds for 32-bit operations, leading to out-of-bounds reads and writes in kernel memory. The vulnerability also affects the Linux 5.4 stable series, starting with v5.4.7, as the introducing commit was backported to that branch. This vulnerability was fixed in 5.6.1, 5.5.14, and 5.4.29. (issue is aka ZDI-CAN-10780) En el kernel de Linux versiones 5.5.0 y más recientes, el verificador bpf (kernel/bpf/verifier.c) no restringió apropiadamente los límites de registro para operaciones de 32 bits, conllevando a lecturas y escrituras fuera de límites en la memoria del kernel. La vulnerabilidad también afecta a la serie estable de Linux versión 5.4, comenzando con la versión v5.4.7, ya que el commit de introducción fue respaldado en esa derivación. • https://github.com/zilong3033/CVE-2020-8835 https://github.com/digamma-ai/CVE-2020-8835-verification https://github.com/SplendidSky/CVE-2020-8835 https://github.com/Prabhashaka/Exploitation-CVE-2020-8835 https://github.com/johnatag/INF8602-CVE-2020-8835 http://www.openwall.com/lists/oss-security/2021/07/20/1 https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=f2d67fec0b43edce8c416101cdc52e71145b5fef https://git.kernel.org/pub/scm/linux/kernel/git/torvald • CWE-125: Out-of-bounds Read CWE-787: Out-of-bounds Write •
CVE-2020-8832 – Ubuntu 18.04 Linux kernel i915 incomplete fix for CVE-2019-14615
https://notcve.org/view.php?id=CVE-2020-8832
The fix for the Linux kernel in Ubuntu 18.04 LTS for CVE-2019-14615 ("The Linux kernel did not properly clear data structures on context switches for certain Intel graphics processors.") was discovered to be incomplete, meaning that in versions of the kernel before 4.15.0-91.92, an attacker could use this vulnerability to expose sensitive information. Se detectó que la solución para el kernel de Linux en Ubuntu versión 18.04 LTS para CVE-2019-14615 ("El kernel de Linux no borró apropiadamente las estructuras de datos en los conmutadores de contexto para determinados procesadores gráficos de Intel") estaba incompleta, lo que significa que en las versiones de kernel anteriores a 4.15.0-91.92, un atacante podría usar esta vulnerabilidad para exponer información confidencial. • https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1862840 https://security.netapp.com/advisory/ntap-20200430-0004 https://usn.ubuntu.com/usn/usn-4302-1 • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor •