CVSS: 6.4EPSS: 0%CPEs: 32EXPL: 0CVE-2020-15705 – GRUB2: avoid loading unsigned kernels when GRUB is booted directly under secureboot without shim
https://notcve.org/view.php?id=CVE-2020-15705
GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed. This only affects systems where the kernel signing certificate has been imported directly into the secure boot database and the GRUB image is booted directly without the use of shim. This issue affects GRUB2 version 2.04 and prior versions. GRUB2 presenta un fallo al comprobar la firma del kernel cuando se inicia directamente sin cuña, permitiendo que el arranque seguro sea omitido. Esto solo afecta a los sistemas en los que el certificado de firma del kernel ha sido importado directamente a la base de datos de arranque seguro y la imagen de GRUB es iniciada directamente sin el uso de cuña. • http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00067.html http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00069.html http://ubuntu.com/security/notices/USN-4432-1 http://www.openwall.com/lists/oss-security/2020/07/29/3 http://www.openwall.com/lists/oss-security/2021/03/02/3 http://www.openwall.com/lists/oss-security/2021/09/17/2 http://www.openwall.com/lists/oss-security/2021/09/17/4 http://www.openwall.com/lists/oss-security&#x • CWE-347: Improper Verification of Cryptographic Signature CWE-440: Expected Behavior Violation •
CVSS: 6.4EPSS: 0%CPEs: 36EXPL: 0CVE-2020-15706 – GRUB2 contains a race condition leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing.
https://notcve.org/view.php?id=CVE-2020-15706
GRUB2 contains a race condition in grub_script_function_create() leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing, leading to arbitrary code execution and secure boot restriction bypass. This issue affects GRUB2 version 2.04 and prior versions. GRUB2 contiene una condición de carrera en la función grub_script_function_create() que conlleva a una vulnerabilidad de uso de la memoria previamente liberada la cual puede ser desencadenada al redefinir una función mientras la misma función ya se está ejecutando, conllevando a una ejecución de código arbitrario y a una omisión de restricción de arranque seguro. Este problema afecta a GRUB2 versiones 2.04 y versiones anteriores • http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html http://ubuntu.com/security/notices/USN-4432-1 http://www.openwall.com/lists/oss-security/2020/07/29/3 https://access.redhat.com/security/vulnerabilities/grub2bootloader https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011 https://security.gentoo.org/ • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') CWE-416: Use After Free •
CVSS: 6.4EPSS: 0%CPEs: 33EXPL: 1CVE-2020-15707 – GRUB2 contained integer overflows when handling the initrd command, leading to a heap-based buffer overflow.
https://notcve.org/view.php?id=CVE-2020-15707
Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow. These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. This issue affects GRUB2 version 2.04 and prior versions. Se detectaron desbordamientos de enteros en las funciones grub_cmd_initrd y grub_initrd_init en el componente efilinux de GRUB2, como se incluye en Debian, Red Hat y Ubuntu (la funcionalidad no está incluida aguas arriba de GRUB2), conllevando a un desbordamiento del búfer en la región heap de la memoria. • http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html http://ubuntu.com/security/notices/USN-4432-1 http://www.openwall.com/lists/oss-security/2020/07/29/3 https://access.redhat.com/security/vulnerabilities/grub2bootloader https://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.html https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011 https://security.gentoo.org/ • CWE-190: Integer Overflow or Wraparound CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') •
CVSS: 7.8EPSS: 97%CPEs: 91EXPL: 0CVE-2019-11477 – Integer overflow in TCP_SKB_CB(skb)->tcp_gso_segs
https://notcve.org/view.php?id=CVE-2019-11477
Jonathan Looney discovered that the TCP_SKB_CB(skb)->tcp_gso_segs value was subject to an integer overflow in the Linux kernel when handling TCP Selective Acknowledgments (SACKs). A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff. Jonathan Looney detectó que el valor TCP_SKB_CB(skb)-mayor que tcp_gso_segs estuvo sujeto a un desbordamiento de enteros en el kernel de Linux durante el manejo del Reconocimiento Selectivo (SACK) de TCP. Un atacante remoto podría usar esto para causar una denegación de servicio. • http://packetstormsecurity.com/files/153346/Kernel-Live-Patch-Security-Notice-LSN-0052-1.html http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html http://www.arubanetworks.com/assets/alert/ARUBA-PSA-2020-010.txt http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20191225-01-kernel-en http://www.openwall.com/lists/oss-security/2019/06/20/3 http://www.openwall.com/lists/oss-security/2019/06/28/2 http://www.openwall.com/lists/oss&# • CWE-190: Integer Overflow or Wraparound CWE-400: Uncontrolled Resource Consumption •
CVSS: 7.5EPSS: 96%CPEs: 90EXPL: 0CVE-2019-11478 – SACK can cause extensive memory use via fragmented resend queue
https://notcve.org/view.php?id=CVE-2019-11478
Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit f070ef2ac66716357066b683fb0baf55f8191a2e. Jonathan Looney descubrió que la implementación de la cola de retransmisión de TCP en tcp_fragment en el kernel de Linux podría estar fragmentada cuando se manejan ciertas secuencias de Reconocimiento Selectivo (SACK) de TCP. Un atacante remoto podría usar esto para causar una denegación de servicio. • http://packetstormsecurity.com/files/153346/Kernel-Live-Patch-Security-Notice-LSN-0052-1.html http://packetstormsecurity.com/files/154408/Kernel-Live-Patch-Security-Notice-LSN-0055-1.html http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html http://www.arubanetworks.com/assets/alert/ARUBA-PSA-2020-010.txt http://www.openwall.com/lists/oss-security/2019/06/28/2 http://www.openwall.com/lists/oss-security/2019/07/06/3 http://www.openwall.com/lists& • CWE-400: Uncontrolled Resource Consumption CWE-770: Allocation of Resources Without Limits or Throttling •