CVE catalog

CVE-2026-97876

Severity: Medium · CVSS 6.4CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Published: Oct 2, 2026, 10:34:23 AM UTC
Updated: Oct 2, 2026, 11:17:39 AM UTC
Source: [NVD] · [CVE record]
EPSS: 0.11% · Oct 25, 2026

A local attacker with control over GRUB's configuration can bypass lockdown restrictions when booting with Secure Boot and load an unsigned GRUB module, while GRUB continues to report lockdown is enabled. The vulnerability is caused by insufficient validation of the MMIO base address passed to the GRUB serial command. GRUB does not validate that the base address corresponds to a UART device, rather than being an arbitrary memory address. This allows an attacker to trick GRUB into writing non-arbitrary data at an attacker-controlled address, including resetting the grub_file_verifiers list in a way that disables the subsequent verification of loaded modules.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	grub2	sid	`2.14-4`	fixed
Debian	grub2	forky	`2.14-4`	fixed
Debian	grub2	trixie	`2.12-9+deb13u2`	vulnerable
Debian	grub2	bookworm	`2.06-13+deb12u2`	not affected
Debian	grub2	bookworm-security	`2.06-13+deb12u1`	not affected

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	grub2	source	sid	`2.14-4`	not yet assigned	Not reported	[1148741]
Debian	grub2	source	forky	`2.14-4`	not yet assigned	Not reported	[1148741]
Debian	grub2	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1148741]
Debian	grub2	source	bookworm	`Not affected`	unimportant	Not reported	[1148741]

[Debian bug #1148741]

OpenFactory catalog packages

[Debian 13 (Trixie)]

[grub2]Affected
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub2-common]Affected
Source package: [grub2]
Details (2)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-common]Affected
Source package: [grub2]
Details (2)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-coreboot]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-coreboot-bin]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-coreboot-dbg]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi]Affected
Source package: [grub2]
Details (2)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-amd64]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-amd64-bin]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-amd64-dbg]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-amd64-signed-template]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-amd64-unsigned]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-arm64]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-arm64-bin]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-arm64-dbg]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-arm64-signed-template]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-arm64-unsigned]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · arm64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-ia32]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-ia32-bin]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13
[grub-efi-ia32-dbg]Affected
Source package: [grub2]
Details (1)
- 2.12-9+deb13u2 · amd64 · trixie
  Affected
  nvd · grub2 · debian · 13

Next results

Observed: Oct 23, 2026, 7:46:40 PM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]