Description
In the Linux kernel, the following vulnerability has been resolved:
mm/huge_memory: fix NULL pointer deference when splitting folio
Commit c010d47f107f ("mm: thp: split huge page to any lower order pages")
introduced an early check on the folio's order via mapping->flags before
proceeding with the split work.
This check introduced a bug: for shmem folios in the swap cache and
truncated folios, the mapping pointer can be NULL. Accessing
mapping->flags in this state leads directly to a NULL pointer dereference.
This commit fixes the issue by moving the check for mapping != NULL before
any attempt to access mapping->flags.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.9 | 6.12.61 |
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 | linux | 6.17.11-1 | — |
| Debian 13 | linux | 6.12.63-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | linux | 6.17.0-19.19 | USN-8094-1 |
| Ubuntu 25.10 | linux-aws +2 | 6.17.0-1009.9 | USN-8094-1 |
| Ubuntu 25.10 | linux-azure +1 | 6.17.0-1010.10 | USN-8094-5, USN-8094-4 |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.10 | linux-realtime | 6.17.0-1008.9 | USN-8094-2 |
| Ubuntu 25.10 | linux-riscv | 6.17.0-19.19.1 | — |
| Ubuntu 24.04 LTS | linux-aws-6.17 | 6.17.0-1009.9~24.04.2 | USN-8094-1 |
| Ubuntu 24.04 LTS | linux-azure-6.17 | 6.17.0-1010.10~24.04.1 | USN-8094-4 |
| Ubuntu 24.04 LTS | linux-gcp-6.17 | 6.17.0-1009.9~24.04.3 | USN-8094-2 |
| Ubuntu 24.04 LTS | linux-hwe-6.17 | 6.17.0-19.19~24.04.2 | USN-8094-1 |
| Ubuntu 24.04 LTS | linux-nvidia-6.17 | 6.17.0-1018.18 | — |
| Ubuntu 24.04 LTS | linux-oem-6.17 | 6.17.0-1017.17 | USN-8152-1 |
| Ubuntu 24.04 LTS | linux-oracle-6.17 | 6.17.0-1009.9~24.04.1 | USN-8094-1 |
| Ubuntu 24.04 LTS | linux-riscv +18 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-6.17 | 6.17.0-19.19.1~24.04.1 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.17 | 6.17.0-1008.9~24.04.1 | USN-8094-3 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.9.1 | SUSE-SU-2026:20220-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | SUSE-SU-2026:20220-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.9.1 | SUSE-SU-2026:20228-1, SUSE-SU-2026:20220-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | SUSE-SU-2026:20220-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | SUSE-SU-2026:20207-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.9.1 | SUSE-SU-2026:20564-1, SUSE-SU-2026:20207-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | openSUSE-SU-2026:20145-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.9.1 | openSUSE-SU-2026:20145-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.63-84.121 | 1:1.0-0.amzn2023 | ALAS2023-2026-1430 |
| Amazon Linux 2023 | perf6.12 +14 | 1:6.12.63-84.121.amzn2023 | ALAS2023-2026-1430 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-108.64.6.3.el10uek | ELSA-2026-50112 |
Advisories 14
- WID-SEC-2025-2868 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 11, 2026
- USN-8094-1 linux, linux-aws, linux-aws-6.17, linux-gcp, linux-hwe-6.17, linux-oracle, linux-oracle-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8094-2 linux-gcp-6.17, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8152-1 linux-oem-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8094-3 linux-realtime-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8094-4 linux-azure, linux-azure-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8094-5 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- SUSE-SU-2026:20564-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- openSUSE-SU-2026:20145-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20228-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20207-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20220-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- ELSA-2026-50112 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Feb 20, 2026
- ALAS2023-2026-1430 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Feb 18, 2026