CVE-2021-3981 – grub2: Incorrect permission in grub.cfg allow unprivileged user to read the file content
https://notcve.org/view.php?id=CVE-2021-3981
A flaw in grub2 was found where its configuration file, known as grub.cfg, is being created with the wrong permission set allowing non privileged users to read its content. This represents a low severity confidentiality issue, as those users can eventually read any encrypted passwords present in grub.cfg. This flaw affects grub2 2.06 and previous versions. This issue has been fixed in grub upstream but no version with the fix is currently released. Se ha encontrado un fallo en grub2 en el que su archivo de configuración, conocido como grub.cfg, es creado con un conjunto de permisos erróneo que permite a usuarios no privilegiado leer su contenido. • http://www.openwall.com/lists/oss-security/2024/01/15/3 https://bugzilla.redhat.com/show_bug.cgi?id=2024170 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AI776L35DDYPCSAAJPJM3ZEQYSFZHBJX https://security.gentoo.org/glsa/202209-12 https://access.redhat.com/security/cve/CVE-2021-3981 • CWE-276: Incorrect Default Permissions •
CVE-2021-3418
https://notcve.org/view.php?id=CVE-2021-3418
If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism. Si los certificados que firmaron grub están instalados en db, grub puede ser arrancado directamente. • https://bugzilla.redhat.com/show_bug.cgi?id=1933757 • CWE-281: Improper Preservation of Permissions •
CVE-2020-25647 – grub2: Out-of-bounds write in grub_usb_device_initialize()
https://notcve.org/view.php?id=CVE-2020-25647
A flaw was found in grub2 in versions prior to 2.06. During USB device initialization, descriptors are read with very little bounds checking and assumes the USB device is providing sane values. If properly exploited, an attacker could trigger memory corruption leading to arbitrary code execution allowing a bypass of the Secure Boot mechanism. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. Se encontró un fallo en grub2 en versiones anteriores a 2.06. • https://bugzilla.redhat.com/show_bug.cgi?id=1886936 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R https://security.gentoo.org/glsa/202104-05 https://security.netapp.com/advisory/ntap-20220325-0001 https://access.redhat.com/security/cve/CVE-2020-25647 • CWE-787: Out-of-bounds Write •
CVE-2020-14372 – grub2: acpi command allows privileged user to load crafted ACPI tables when Secure Boot is enabled
https://notcve.org/view.php?id=CVE-2020-14372
A flaw was found in grub2 in versions prior to 2.06, where it incorrectly enables the usage of the ACPI command when Secure Boot is enabled. This flaw allows an attacker with privileged access to craft a Secondary System Description Table (SSDT) containing code to overwrite the Linux kernel lockdown variable content directly into memory. The table is further loaded and executed by the kernel, defeating its Secure Boot lockdown and allowing the attacker to load unsigned code. The highest threat from this vulnerability is to data confidentiality and integrity, as well as system availability. Se encontró un fallo en grub2 en versiones anteriores a 2.06, donde habilita incorrectamente el uso del comando ACPI cuando Secure Boot está habilitado. • https://github.com/kukrimate/CVE-2020-14372 https://access.redhat.com/security/vulnerabilities/RHSB-2021-003 https://bugzilla.redhat.com/show_bug.cgi?id=1873150 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R https://security.gentoo.org/glsa/202104-05 https://security.netapp.com/advisory/ntap-20210416-0004 https://access.redhat.com/security/cve/CVE-2020-14372 • CWE-184: Incomplete List of Disallowed Inputs •
CVE-2021-20225 – grub2: Heap out-of-bounds write in short form option parser
https://notcve.org/view.php?id=CVE-2021-20225
A flaw was found in grub2 in versions prior to 2.06. The option parser allows an attacker to write past the end of a heap-allocated buffer by calling certain commands with a large number of specific short forms of options. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. Se encontró un fallo en grub2 en versiones anteriores a 2.06. El analizador de opciones permite a un atacante escribir más allá del final de un búfer asignado a la pila al llamar a determinados comandos con una gran cantidad de formularios de opciones cortos específicos. • https://bugzilla.redhat.com/show_bug.cgi?id=1924696 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R https://security.gentoo.org/glsa/202104-05 https://security.netapp.com/advisory/ntap-20220325-0001 https://access.redhat.com/security/cve/CVE-2021-20225 • CWE-787: Out-of-bounds Write •