shim

shim, a first-stage UEFI bootloader shim is a trivial EFI application that, when run, attempts to open and execute another application. It will initially attempt to do this via the standard EFI LoadImage and StartImage calls. If these fail because Secure Boot is enabled and the binary is not sign...

shim-review

This repo is for review of requests for signing shim. To create a request for review: clone this repo preferably fork it edit the template below add the shim.efi to be signed add build logs add any additional binaries/certificates/SHA256 hashes that may be needed commit all of that tag it with a...

CVE-2020-14372

CVE-2020-14372: Bypassing not so Secure Boot with one "simple trick" Vulnerability details One day I typed "help" into GRUB2's console and saw some really "fun" commands: readbyte ADDR: Read 8-bit value from ADDR writebyte ADDR VAL: Write 8-bit value VAL to ADDR I immediately thought I found the...

CVE-2025-0690

CVE-2025-0690: Integer Overflow Vulnerability in GRUB2 🛡️ Overview CVE-2025-0690 is a critical integer overflow vulnerability in the GRUB2 boot loader, allowing arbitrary code execution and Secure Boot bypass. This flaw affects systems that rely on GRUB2 for secure boot, exposing the system before...

slot2

slot2 slot2: a two-stage UEFI GRUB2 bootkit that persists a pre-OS networked implant on Amazon Linux 2023 on AWS EC2 UEFI x8664. by cenobyte [email protected] 2026 https://github.com/cenobyte-vincit/slot2 Summary slot2 is a bootkit for Amazon Linux 2023 on EC2. The AWS EC2 UEFI firmware load...

CLEANSTART-2024-AP29211 flaw was found in grub2 in versions prior to 2

Security vulnerability affects the grub package. A flaw was found in grub2 in versions prior to 2...

CLEANSTART-2024-ST49849 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 inclu...

Security vulnerability affects the grub package. Integer overflows were discovered in the functions grubcmdinitrd and grubinitrdinit 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...

CLEANSTART-2024-XM31676 GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed

Security vulnerability affects the grub package. GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed...

Astra Linux – Vulnerability in grub2

Integer underflow in grubnetrecvip4packets; A malicious IP packet can cause an integer underflow in the grubnetrecvip4packets function, affecting the rsm-totallen value. Under certain circumstances, the totallen value may wrap around to a small integer number, which will be used in memory...

Astra Linux – Vulnerability in grub2

The GRUB2’s shimlock verifier allows non-kernel files to be loaded on shim-powered secure boot systems. Allowing such files to be loaded may lead to unverified code and modules being loaded in GRUB2, thereby breaking the secure boot trust-chain...

Astra Linux – Vulnerability in grub2

A flaw was discovered in grub2 in versions prior to 2.06. The rmmod implementation allows the unloading of a module that serves as a dependency without checking whether any other dependent modules are still loaded, leading to a “use-after-free” scenario. This could allow arbitrary code to be...

Astra Linux – Vulnerability in grub2

A flaw was discovered in grub2 in versions prior to 2.06. The Setparamprefix function in the menu rendering code performs a length calculation based on the assumption that expressing a single quoted character would require 3 characters. However, in reality, it requires 4 characters. This allows a...

Rocky Linux 8.6 [CIQ] Security Update: grub2-common / grub2-efi-aa64 / grub2-efi-aa64-cdboot / etc Multiple Vulnerabilities (ciqsa-2026_1601)

The Rocky Linux 8.6 host has packages installed that are affected by multiple vulnerabilities as referenced in the CIQ ciqsa-20261601 advisory. This advisory aggregates security fixes for the grub2 SRPM in CIQ LTS 8.6. It addresses 26 CVEs: CVE-2021-3981, CVE-2021-20233, CVE-2020-14310,...

CVE-2026-97876

A flaw was found in GRUB2. The bootloader insufficiently validates memory addresses passed to the serial configuration command, allowing arbitrary system memory to be targeted instead of a legitimate serial communication device. A local attacker with control over GRUB's boot configuration can...

Rocky Linux 9 [CIQ] Security Update: grub2-common / grub2-debuginfo / grub2-debugsource / grub2-efi-aa64 / etc (crlsa-2025_20532)

The Rocky Linux 9 host has packages installed that are affected by a vulnerability as referenced in the CIQ crlsa-202520532 advisory. grub2: grub-core/gettext: Integer overflow leads to Heap OOB Write. CVE-2024-45777 Tenable has extracted the preceding description block directly from the CIQ...

Rocky Linux 8 [CIQ] Security Update: fwupd / fwupd-debuginfo / fwupd-debugsource Multiple Vulnerabilities (crlsa-2021_2566)

The Rocky Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the CIQ crlsa-20212566 advisory. grub2: acpi command allows privileged user to load crafted ACPI tables when Secure Boot is enabled CVE-2020-14372 grub2: Use-after-free in rmmod command...

Rocky Linux 9 [CIQ] Security Update: grub2-common / grub2-efi-aa64 / grub2-efi-aa64-cdboot / etc Multiple Vulnerabilities (crlsa-2023_0752)

The Rocky Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the CIQ crlsa-20230752 advisory. grub2: Buffer overflow in grubfontconstructglyph can lead to out-of-bound write and possible secure boot bypass CVE-2022-2601 grub2: Heap based out-of-boun...

Rocky Linux 8 [CIQ] Security Update: grub2-common / grub2-efi-aa64 / grub2-efi-aa64-cdboot / etc (crlsa-2025_3367)

The Rocky Linux 8 host has packages installed that are affected by a vulnerability as referenced in the CIQ crlsa-20253367 advisory. grub2: net: Out-of-bounds write in grubnetsearchconfigfile CVE-2025-0624 Tenable has extracted the preceding description block directly from the CIQ security...

CentOS Linux 8.5 [TuxCare] Security Update: grub2-common / grub2-efi-ia32 / grub2-efi-ia32-cdboot / etc (CENTOS8.5:CLSA-2026:1771955086)

The CentOS Linux 8.5 host has packages installed that are affected by a vulnerability as referenced in the TuxCare CENTOS8.5:CLSA-2026:1771955086 advisory. - A Use-After-Free vulnerability has been discovered in GRUB's gettext module. This flaw stems from a programming error where the gettext...

Rocky Linux 8.6 [CIQ] Security Update: grub2-common / grub2-debuginfo / grub2-efi-aa64 / etc Multiple Vulnerabilities (ciqsa-2026_0881)

The Rocky Linux 8.6 host has packages installed that are affected by multiple vulnerabilities as referenced in the CIQ ciqsa-20260881 advisory. This advisory aggregates security fixes for the grub2 SRPM in CIQ LTS 8.6. It addresses 2 CVEs: CVE-2022-3775, CVE-2022-2601. Tenable has extracted the...