
CVE-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
29 Jul 2020 — 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 afe... • http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00067.html • CWE-347: Improper Verification of Cryptographic Signature CWE-440: Expected Behavior Violation •

CVE-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
28 Jul 2020 — 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 de... • http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') CWE-416: Use After Free •

CVE-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
28 Jul 2020 — 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 ... • http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html • CWE-190: Integer Overflow or Wraparound CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') •

CVE-2019-11477 – Integer overflow in TCP_SKB_CB(skb)->tcp_gso_segs
https://notcve.org/view.php?id=CVE-2019-11477
17 Jun 2019 — 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 ... • https://github.com/sasqwatch/cve-2019-11477-poc • CWE-190: Integer Overflow or Wraparound CWE-400: Uncontrolled Resource Consumption •

CVE-2019-11478 – SACK can cause extensive memory use via fragmented resend queue
https://notcve.org/view.php?id=CVE-2019-11478
17 Jun 2019 — 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_fr... • http://packetstormsecurity.com/files/153346/Kernel-Live-Patch-Security-Notice-LSN-0052-1.html • CWE-400: Uncontrolled Resource Consumption CWE-770: Allocation of Resources Without Limits or Throttling •