Description
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Clear Present bit before tearing down PASID entry
The Intel VT-d Scalable Mode PASID table entry consists of 512 bits (64
bytes). When tearing down an entry, the current implementation zeros the
entire 64-byte structure immediately using multiple 64-bit writes.
Since the IOMMU hardware may fetch these 64 bytes using multiple
internal transactions (e.g., four 128-bit bursts), updating or zeroing
the entire entry while it is active (P=1) risks a "torn" read. If a
hardware fetch occurs simultaneously with the CPU zeroing the entry, the
hardware could observe an inconsistent state, leading to unpredictable
behavior or spurious faults.
Follow the "Guidance to Software for Invalidations" in the VT-d spec
(Section 6.5.3.3) by implementing the recommended ownership handshake:
1. Clear only the 'Present' (P) bit of the PASID entry.
2. Use a dma_wmb() to ensure the cleared bit is visible to hardware
before proceeding.
3. Execute the required invalidation sequence (PASID cache, IOTLB, and
Device-TLB flush) to ensure the hardware has released all cached
references.
4. Only after the flushes are complete, zero out the remaining fields
of the PASID entry.
Also, add a dma_wmb() in pasid_set_present() to ensure that all other
fields of the PASID entry are visible to the hardware before the Present
bit is set.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.0 | 6.1.191 |
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 | 6.18.14-1 | — |
| Debian 13 | linux | 6.12.85-1 | — |
| Debian 12 | linux | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu 25.10 | linux +8 | No fix yet | — |
| Ubuntu 24.04 LTS | linux +43 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1035.38 | USN-8781-1 |
| Ubuntu 22.04 LTS | linux +59 | No fix yet | — |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime +3 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime +2 | No fix yet | — |
| Ubuntu Pro FIPS 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux +21 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | linux-aws-5.4 +6 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | rv +76 | 6.12.0-211.58.1.el10_2 | RHSA-2026:70498 |
| RHEL 9 | rv +75 | 5.14.0-687.50.1.el9_8 | RHSA-2026:70459 |
| RHEL 8 | kernel-rt +12 | 4.18.0-553.166.1.rt7.507.el8_10 | RHSA-2026:70403 |
| RHEL 8 | perf +26 | 4.18.0-553.166.1.el8_10 | RHSA-2026:70402 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | rv +61 | 6.12.0-211.58.1.el10_2 | ALSA-2026:70498 |
| AlmaLinux 9 | rv +73 | 5.14.0-687.50.1.el9_8 | ALSA-2026:70459 |
| AlmaLinux 8 | kernel-rt +9 | 4.18.0-553.166.1.rt7.507.el8_10 | ALSA-2026:70403 |
| AlmaLinux 8 | perf +24 | 4.18.0-553.166.1.el8_10 | ALSA-2026:70402 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | kernel | 6.12.0-211.58.1.el10_2 | RLSA-2026:70498 |
| Rocky Linux 9 | kernel | 5.14.0-687.50.1.el9_8 | RLSA-2026:70459 |
| Rocky Linux 8 | kernel | 4.18.0-553.166.1.el8_10 | RLSA-2026:70402 |
| Rocky Linux 8 | kernel-rt | 4.18.0-553.166.1.rt7.507.el8_10 | RLSA-2026:70403 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +7 | 6.4.0-150700.53.63.1 | SUSE-SU-2026:2722-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.63.1.150700.17.37.1 | SUSE-SU-2026:2722-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.36.1 | SUSE-SU-2026:22835-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | SUSE-SU-2026:22835-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.36.1 | SUSE-SU-2026:22835-1, SUSE-SU-2026:22812-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | SUSE-SU-2026:22835-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | SUSE-SU-2026:22769-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.36.1 | SUSE-SU-2026:22769-1, SUSE-SU-2026:22742-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-48.1.21.25 | SUSE-SU-2026:22460-1 |
| SLE Micro 6.1 | kernel-rt +4 | 6.4.0-48.1 | SUSE-SU-2026:22460-1, SUSE-SU-2026:22458-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-48.1.21.25 | SUSE-SU-2026:22436-1 |
| SLE Micro 6.0 | kernel-rt +4 | 6.4.0-48.1 | SUSE-SU-2026:22436-1, SUSE-SU-2026:22433-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.63.1 | SUSE-SU-2026:2722-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_17 | 1-150700.1.3.1 | SUSE-SU-2026:2799-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_17 | 1-150700.15.3.1 | SUSE-SU-2026:2722-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.62.1 | SUSE-SU-2026:2799-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.36.1.160000.2.17 | openSUSE-SU-2026:21388-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.36.1 | openSUSE-SU-2026:21388-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.77-99.140 +1 | 1:1.0-0.amzn2023 | ALAS2023-2026-1543, ALAS2023-2026-1514 |
| Amazon Linux 2023 | perf6.12 +14 | 1:6.12.77-99.140.amzn2023 | ALAS2023-2026-1543 |
| Amazon Linux 2023 | perf6.18 +14 | 1:6.18.15-14.217.amzn2023 | ALAS2023-2026-1514 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | rv +29 | 6.12.0-211.60.1.el10_2 | ELSA-2026-70498 |
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-204.92.4.2.el10uek | ELSA-2026-50372 |
| Oracle Linux 9 | rv +28 | 5.14.0-687.50.1.el9_8 | ELSA-2026-70459 |
| Oracle Linux 8 | perf +19 | 4.18.0-553.168.1.el8_10 | ELSA-2026-70402 |
Advisories 31
- WID-SEC-2026-1700 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8781-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- ALSA-2026:70498 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:70459 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:70403 Important: kernel-rt security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:70402 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2026:70498 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:70459 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:70403 Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2026:70402 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- ELSA-2026-70498 Important: kernel security, bug fix, and enhancement update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Oct 5, 2026
- ELSA-2026-70402 Important: kernel security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Oct 2, 2026
- RLSA-2026:70459 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 24, 2026
- RLSA-2026:70498 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 24, 2026
- RLSA-2026:70402 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 24, 2026
- RLSA-2026:70403 Important: kernel-rt security, bug fix, and enhancement update Rocky Linux Security Advisories · Sep 24, 2026
- ELSA-2026-70459 Important: kernel security, bug fix, and enhancement update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Sep 24, 2026
- SUSE-SU-2026:22835-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- SUSE-SU-2026:22812-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 28, 2026
- openSUSE-SU-2026:21388-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 24, 2026
- SUSE-SU-2026:22769-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 23, 2026
- SUSE-SU-2026:22742-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 23, 2026
- SUSE-SU-2026:2799-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- SUSE-SU-2026:22458-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 4, 2026
- SUSE-SU-2026:22460-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 4, 2026
- SUSE-SU-2026:22433-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 3, 2026
- SUSE-SU-2026:22436-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 3, 2026
- SUSE-SU-2026:2722-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 2, 2026
- ELSA-2026-50372 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 2, 2026
- ALAS2023-2026-1514 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
- ALAS2023-2026-1543 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 16, 2026
References
- https://git.kernel.org/stable/c/bed36f5657d34ae982d48045a75bff6113790cf9
- https://git.kernel.org/stable/c/c36b0515c6445bd137ec8ad86ef5470c45d6e4bf
- https://git.kernel.org/stable/c/a84d30e8d2bacd21782a6481158b7c9c552f4868
- https://git.kernel.org/stable/c/821807c167b7b48a41b95b6607c6b9f97600f7d9
- https://git.kernel.org/stable/c/949d71666e9dd19f21e7b4b53a88cd2c5b902858
- https://git.kernel.org/stable/c/75ed00055c059dedc47b5daaaa2f8a7a019138ff