Description
A flaw was found in grub2. When performing a symlink lookup, the grub's UFS module checks the inode's data size to allocate the internal buffer to read the file content, however, it fails to check if the symlink data size has overflown. When this occurs, grub_malloc() may be called with a smaller value than needed. When further reading the data from the disk into the buffer, the grub_ufs_lookup_symlink() function will write past the end of the allocated size. An attack can leverage this by crafting a malicious filesystem, and as a result, it will corrupt data stored in the heap, allowing for arbitrary code execution used to by-pass secure boot mechanisms.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | grub2 | ≤ 2.12 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| 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 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | grub2 +15 | 1:2.12-15.el10_0 | RHSA-2025:16154 |
| RHEL 9 | grub2 +15 | 1:2.06-104.el9_6 | RHSA-2025:6990 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | grub2-common +4 | 1:2.12-15.el10_0.alma.1 | ALSA-2025:16154 |
| AlmaLinux 9 | grub2-pc +14 | 1:2.06-104.el9_6.alma.1 | ALSA-2025:6990 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | grub2 | 1:2.12-15.el10_0 | RLSA-2025:16154 |
| Rocky Linux 9 | grub2 | 1:2.06-104.el9_6 | RLSA-2025:6990 |
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 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | grub2-pc +12 | 1:2.12-15.0.1.el10_0 | ELSA-2025-16154 |
| Oracle Linux 9 | grub2-pc +12 | 1:2.06-104.0.1.el9_6 | ELSA-2025-6990 |
Advisories 19
- ALSA-2025:6990 Moderate: grub2 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2025:16154 Moderate: grub2 security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2025:16154 Red Hat Security Advisory: grub2 security update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2025:6990 Red Hat Security Advisory: grub2 security update Red Hat Security Advisories (RHSA) · Jul 21, 2026
- 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
- RLSA-2025:16154 Moderate: grub2 security update Rocky Linux Security Advisories · Oct 8, 2025
- RLSA-2025:6990 Moderate: grub2 security update Rocky Linux Security Advisories · Oct 7, 2025
- ELSA-2025-16154 Moderate: grub2 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Sep 18, 2025
- ELSA-2025-6990 Moderate: grub2 security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · May 16, 2025
- 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
References
- RHSA-2025:16154 vendor-advisory
- RHSA-2025:6990 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2025-0677 vdb-entry
- RHBZ#2346116 issue-tracking
- https://lists.gnu.org/archive/html/grub-devel/2025-02/msg00024.html