CVSS: 8.8EPSS: 0%CPEs: 10EXPL: 2CVE-2021-3490 – Linux kernel eBPF bitwise ops ALU32 bounds tracking
https://notcve.org/view.php?id=CVE-2021-3490
The eBPF ALU32 bounds tracking for bitwise ops (AND, OR and XOR) in the Linux kernel did not properly update 32-bit bounds, which could be turned into out of bounds reads and writes in the Linux kernel and therefore, arbitrary code execution. This issue was fixed via commit 049c4e13714e ("bpf: Fix alu32 const subreg bound tracking on bitwise operations") (v5.13-rc4) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. The AND/OR issues were introduced by commit 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") (5.7-rc1) and the XOR variant was introduced by 2921c90d4718 ("bpf:Fix a verifier failure with xor") ( 5.10-rc1). El seguimiento de los límites de la ALU32 de eBPF para las operaciones por bits (AND, OR y XOR) en el kernel de Linux no actualizaba correctamente los límites de 32 bits, lo que podía convertirse en lecturas y escrituras fuera de los límites en el kernel de Linux y, por tanto, en la ejecución de código arbitrario. Este problema fue corregido a través del commit 049c4e13714e ("bpf: Fix alu32 const subreg bound tracking on bitwise operations") (v5.13-rc4) y retrocedido a los kernels estables en v5.12.4, v5.11.21 y v5.10.37. • https://github.com/pivik271/CVE-2021-3490 http://packetstormsecurity.com/files/164015/Linux-eBPF-ALU32-32-bit-Invalid-Bounds-Tracking-Local-Privilege-Escalation.html https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=049c4e13714ecbca567b4d5f6d563f05d431c80e https://security.netapp.com/advisory/ntap-20210716-0004 https://ubuntu.com/security/notices/USN-4949-1 https://ubuntu.com/security/notices/USN-4950-1 https://www.openwall.com/lists/oss-security/2021/05/11/11 https:/ • CWE-20: Improper Input Validation CWE-125: Out-of-bounds Read CWE-787: Out-of-bounds Write •
CVSS: 8.8EPSS: 0%CPEs: 6EXPL: 0CVE-2021-3491 – Linux kernel io_uring PROVIDE_BUFFERS MAX_RW_COUNT bypass
https://notcve.org/view.php?id=CVE-2021-3491
The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1). El subsistema io_uring del kernel de Linux permitía saltarse el límite MAX_RW_COUNT en la operación PROVIDE_BUFFERS, lo que llevaba a utilizar valores negativos en mem_rw al leer /proc//mem. • https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d1f82808877bb10d3deee7cf3374a4eb3fb582db https://security.netapp.com/advisory/ntap-20210716-0004 https://ubuntu.com/security/notices/USN-4949-1 https://ubuntu.com/security/notices/USN-4950-1 https://www.openwall.com/lists/oss-security/2021/05/11/13 https://www.zerodayinitiative.com/advisories/ZDI-21-589 • CWE-131: Incorrect Calculation of Buffer Size CWE-787: Out-of-bounds Write •
CVSS: 7.5EPSS: 2%CPEs: 10EXPL: 0CVE-2020-15078
https://notcve.org/view.php?id=CVE-2020-15078
OpenVPN 2.5.1 and earlier versions allows a remote attackers to bypass authentication and access control channel data on servers configured with deferred authentication, which can be used to potentially trigger further information leaks. OpenVPN versiones 2.5.1 y anteriores, permiten a atacantes remotos omitir la autenticación y los datos del canal de control de acceso en servidores configurados con autenticación diferida, que pueden ser usados para desencadenar potencialmente más fugas de información • https://community.openvpn.net/openvpn/wiki/CVE-2020-15078 https://community.openvpn.net/openvpn/wiki/SecurityAnnouncements https://lists.debian.org/debian-lts-announce/2022/05/msg00002.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GJUXEYHUPREEBPX23VPEKMFXUPVO3PMU https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JGEGLC4YGBDN5CGHTNWN2GH6DJJA36T2 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PLDB3OBQ • CWE-305: Authentication Bypass by Primary Weakness CWE-306: Missing Authentication for Critical Function •
CVSS: 8.8EPSS: 0%CPEs: 3EXPL: 13CVE-2021-3493 – Linux Kernel Privilege Escalation Vulnerability
https://notcve.org/view.php?id=CVE-2021-3493
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges. La implementación de overlayfs en el kernel de Linux no comprobó apropiadamente con respecto a los espacios de nombre de los usuarios, la configuración de las capacidades de los archivos en un sistema de archivos subyacente. Debido a la combinación de los espacios de nombre de usuarios no privilegiados junto con un parche incluido en el kernel de Ubuntu para permitir montajes de superposición no privilegiados, un atacante podría usar esto para alcanzar privilegios elevados The overlayfs stacking file system in Linux kernel does not properly validate the application of file capabilities against user namespaces, which could lead to privilege escalation. • https://github.com/briskets/CVE-2021-3493 https://github.com/inspiringz/CVE-2021-3493 https://github.com/oneoy/CVE-2021-3493 https://github.com/cerodah/overlayFS-CVE-2021-3493 https://github.com/derek-turing/CVE-2021-3493 https://github.com/puckiestyle/CVE-2021-3493 https://github.com/smallkill/CVE-2021-3493 https://github.com/Abdennour-py/CVE-2021-3493 https://github.com/fei9747/CVE-2021-3493 https://github.com/ptkhai15/OverlayFS---CVE-2021-3493 https://git • CWE-270: Privilege Context Switching Error CWE-863: Incorrect Authorization •
CVSS: 8.8EPSS: 0%CPEs: 3EXPL: 1CVE-2021-3492 – Ubuntu linux kernel shiftfs file system double free vulnerability
https://notcve.org/view.php?id=CVE-2021-3492
Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562. Shiftfs, un sistema de archivos de apilamiento fuera del árbol incluido en los kernels de Ubuntu Linux, no manejaba apropiadamente los fallos que ocurrían durante la función copy_from_user(). • https://github.com/synacktiv/CVE-2021-3492 http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333 https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6 https://ubuntu.com/security/notices/USN-4917-1 https://www.openwall.com/lists/oss-security/2021/04/16/2 https:&#x • CWE-401: Missing Release of Memory after Effective Lifetime CWE-415: Double Free •