Description
A flaw was found in grub2. When performing a symlink lookup from a romfs filesystem, grub's romfs filesystem module uses user-controlled parameters from the filesystem geometry to determine the internal buffer size, however, it improperly checks for integer overflows. A maliciously crafted filesystem may lead some of those buffer size calculations to overflow, causing it to perform a grub_malloc() operation with a smaller size than expected. As a result, the grub_romfs_read_symlink() may cause out-of-bounds writes when the calling grub_disk_read() function. This issue may be leveraged to corrupt grub's internal critical data and can result in arbitrary code execution by-passing secure boot protections.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | grub2 | ≤ 2.12 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | grub2 | 2.12-6 | — |
| Debian 13 | grub2 | 2.12-6 | — |
| Debian 12 | grub2 | 2.06-13+deb12u2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | grub2-signed +1 | No fix yet | — |
| Ubuntu 26.04 LTS | grub2-signed +1 | No fix yet | — |
| Ubuntu 25.10 | grub2-signed +1 | No fix yet | — |
| Ubuntu 24.04 LTS | grub2-signed +1 | No fix yet | — |
| Ubuntu 22.04 LTS | grub2-signed +1 | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | grub2-signed +1 | No fix yet | — |
| Ubuntu 18.04 LTS | grub2-signed +1 | No fix yet | — |
| Ubuntu 16.04 LTS | grub2-signed +1 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | grub2 +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | grub2 | 2.12-150600.8.18.2 | SUSE-SU-2025:0586-1 |
| SLES 15 SP5 | grub2 | 2.06-150500.29.43.2 | SUSE-SU-2025:0587-1 |
| SLES 15 SP4 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SLES 15 SP3 | grub2 | 2.04-150300.22.52.3 | SUSE-SU-2025:0607-1 |
| SLES 12 SP5 | grub2 | 2.02-181.2 | SUSE-SU-2025:0629-1 |
Show 18 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP5 | grub2 | 2.06-150500.29.43.2 | SUSE-SU-2025:0587-1 |
| SLES for SAP 15 SP4 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SLES for SAP 15 SP3 | grub2 | 2.04-150300.22.52.3 | SUSE-SU-2025:0607-1 |
| SLE Micro 6.1 | grub2 | 2.12-slfo.1.1_2.1 | SUSE-SU-2025:20863-1 |
| SLE Micro 6.0 | grub2 | 2.12~rc1-6.1 | SUSE-SU-2025:20511-1 |
| SLE Micro 5.5 | grub2 | 2.06-150500.29.43.2 | SUSE-SU-2025:0587-1 |
| SLE Micro 5.4 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SLE Micro 5.3 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SLE Micro 5.2 | grub2 | 2.04-150300.22.52.3 | SUSE-SU-2025:0607-1 |
| SLE Micro 5.1 | grub2 | 2.04-150300.3.11.1 | SUSE-SU-2025:01961-1 |
| SLE HPC 15 SP5 | grub2 | 2.06-150500.29.43.2 | SUSE-SU-2025:0587-1 |
| SLE HPC 15 SP4 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SLE HPC 15 SP3 | grub2 | 2.04-150300.22.52.3 | SUSE-SU-2025:0607-1 |
| SUSE Manager Server Module 4.3 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SUSE Manager Server 4.3 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SUSE Manager Proxy Module 4.3 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SUSE Manager Proxy 4.3 | grub2 | 2.06-150400.11.55.2 | SUSE-SU-2025:0588-1 |
| SUSE Enterprise Storage 7.1 | grub2 | 2.04-150300.22.52.3 | SUSE-SU-2025:0607-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | grub2 | 2.12-35.1 | openSUSE-SU-2025:14822-1 |
| openSUSE Leap 15.6 | grub2 | 2.12-150600.8.18.2 | SUSE-SU-2025:0586-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | grub2-pc +16 | 1:2.06-61.amzn2023.0.16 | ALAS2023-2025-937 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | grub2 | 2.06-25 | — |
| Azure Linux 2 (CBL-Mariner) | grub2 | 2.06-15 | — |
Advisories 11
- WID-SEC-2025-0396 Grub: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 15, 2026
- SUSE-SU-2025:20863-1 Security update for grub2 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20511-1 Security update for grub2 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:01961-1 Security update for grub2 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:0586-1 Security update for grub2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:0629-1 Security update for grub2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:0607-1 Security update for grub2 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:0587-1 Security update for grub2 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2025:14822-1 grub2-2.12-35.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- SUSE-SU-2025:0588-1 Security update for grub2 SUSE / openSUSE Security Updates · May 2, 2025
- ALAS2023-2025-937 Moderate: grub2 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Apr 14, 2025