Description
In the Linux kernel, the following vulnerability has been resolved:
nfsd: defer vfree of compound ops to fix rpc_status UAF
The rpc_status netlink dumpit walks every in-flight svc_rqst under
rcu_read_lock and, for NFSv4 requests, reads opnums out of
args->ops[]. But args->ops is a separate vmalloc buffer freed
synchronously by vfree() in nfsd4_release_compoundargs() at the end
of every compound. The dumpit's rcu_read_lock pins the svc_rqst
struct itself (freed via kfree_rcu), but nothing defers the vfree
of the ops buffer across the RCU grace period. A concurrent compound
completion can therefore free the buffer while the dumpit is reading
it — a use-after-free on vmalloc memory.
The trailing seqcount recheck (smp_load_acquire of rq_status_counter)
cannot undo a load that already retired against freed memory.
Fix by replacing vfree(args->ops) with kvfree_rcu_mightsleep(), which
defers the free until after an RCU grace period. This makes the
existing rcu_read_lock in the dumpit sufficient to protect the read.
The tradeoff is that completed compound ops buffers (up to
200 * sizeof(struct nfsd4_op)) persist in memory slightly longer,
across one grace period, before being reclaimed.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.7 | 6.12.109 |
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 | 7.2.6-1 | — |
| Debian 13 | linux | 6.12.111-1 | — |
| Debian 12 | linux-6.12 | 6.12.111-1~deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1036.41 | — |
| Ubuntu 26.04 LTS | linux | 7.0.0-42.42 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-aws | 7.0.0-1016.17 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-azure | 7.0.0-1020.21 | USN-9019-1 |
| Ubuntu 26.04 LTS | linux-azure-fde | 7.0.0-1019.19 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-gcp | 7.0.0-1016.18 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-gke | 7.0.0-1010.11 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-ibm +1 | 7.0.0-1017.17 | USN-8960-1, USN-8959-1 |
| Ubuntu 26.04 LTS | linux-nvidia +1 | No fix yet | — |
| Ubuntu 26.04 LTS | linux-oracle | 7.0.0-1015.16 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-raspi | 7.0.0-1023.23 | USN-9021-1 |
| Ubuntu 26.04 LTS | linux-realtime | 7.0.0-43.43.1 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-riscv | 7.0.0-42.42.1 | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-149.149 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1069.74 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-aws-7.0 | 7.0.0-1017.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1073.82 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1071.78 | USN-9039-1 |
| Ubuntu 24.04 LTS | linux-azure-fde-7.0 | 7.0.0-1019.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1073.81 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-gcp-7.0 | 7.0.0-1017.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1068.77 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1053.57 | USN-9023-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-42.42~24.04.1 | USN-8959-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1069.70 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-149.149.1 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1067.70 | USN-9024-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1067.70.1 | USN-9040-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1038.42 | USN-9002-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1067.71 | USN-9022-1 |
| Ubuntu 24.04 LTS | linux-oracle-7.0 | 7.0.0-1016.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1068.72 | USN-9025-1 |
| Ubuntu 24.04 LTS | linux-riscv +31 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-7.0 | 7.0.0-42.42.1~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-vmware | 6.8.0-1010.10 | USN-9022-1 |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1069.74~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1073.82~22.04.1 | USN-9026-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1071.78~22.04.1 | USN-9026-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1073.81~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-149.149~22.04.1 | USN-9066-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1069.70~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-149.149.1~22.04.1 | USN-9024-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1067.71~22.04.1 | USN-9025-1 |
| Ubuntu 22.04 LTS | linux-riscv +33 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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-raspi-realtime | 6.8.0-2056.58 | USN-9025-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1064.65 | USN-9023-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1064.65~22.04.1 | USN-9024-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1069.74+fips1 | USN-9023-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1073.82+fips1 | USN-9022-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1073.81+fips1 | USN-9023-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | rv +77 | 6.12.0-211.64.1.el10_2 | RHSA-2026:77690 |
| RHEL 9 | rv +75 | 5.14.0-687.56.1.el9_8 | RHSA-2026:77689 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Shadow Migration Toolkit 10 | kernel-modules-internal | 6.12.0-211.64.1.el10_2 | RHSA-2026:77690 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | rv +74 | 6.12.0-211.64.1.el10_2 | ALSA-2026:77690 |
| AlmaLinux 9 | rv +73 | 5.14.0-687.56.1.el9_8 | ALSA-2026:77689 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | kernel | 6.12.0-211.64.1.el10_2 | RLSA-2026:77690 |
| Rocky Linux 9 | kernel | 5.14.0-687.56.1.el9_8 | RLSA-2026:77689 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.39.1 | SUSE-SU-2026:24235-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.39.1.160000.2.26 | SUSE-SU-2026:24235-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.39.1 | SUSE-SU-2026:24235-1, SUSE-SU-2026:24197-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.39.1.160000.2.26 | SUSE-SU-2026:24235-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.39.1.160000.2.26 | SUSE-SU-2026:24184-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.39.1 | SUSE-SU-2026:24184-1, SUSE-SU-2026:24179-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 7.2.6-1.1 | openSUSE-SU-2026:11805-1 |
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.39.1.160000.2.25 | openSUSE-SU-2026:22091-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.39.1 | openSUSE-SU-2026:22091-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.51-120.162 +1 | 1:1.0-0.amzn2023 | ALAS2023-2026-3196, ALAS2023-2026-3187 |
| Amazon Linux 2023 | perf6.12 +11 | 1:6.12.110-135.201.amzn2023 | ALAS2023-2026-3196 |
| Amazon Linux 2023 | perf6.18 +12 | 1:6.18.51-120.162.amzn2023 | ALAS2023-2026-3187 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | rv +29 | 6.12.0-211.64.1.el10_2 | ELSA-2026-77690 |
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-207.111.5.1.el10uek | ELSA-2026-500374 |
| Oracle Linux 9 | rv +28 | 5.14.0-687.56.1.el9_8 | ELSA-2026-77689 |
Advisories 32
- USN-9066-1 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9021-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9022-1 linux, linux-aws, linux-azure, linux-azure-fips, linux-gcp, linux-gke, linux-ibm, linux-lowlatency, linux-oracle, linux-vmware vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9024-1 linux-aws-6.8, linux-gcp-6.8, linux-ibm-6.8, linux-lowlatency-hwe-6.8, linux-nvidia, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9026-1 linux-azure-6.8, linux-azure-fde-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9039-1 linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- WID-SEC-2026-3321 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-9040-1 linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9020-1 linux-aws-7.0, linux-azure-fde, linux-azure-fde-7.0, linux-gcp-7.0, linux-gke, linux-oracle-7.0, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8959-1 linux, linux-aws, linux-gcp, linux-hwe-7.0, linux-ibm, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9025-1 linux-oracle-6.8, linux-raspi, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9023-1 linux-aws-fips, linux-gcp-fips, linux-gkeop, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9019-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-8960-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- USN-9002-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 12, 2026
- ALSA-2026:77689 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:77690 Important: kernel security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 29, 2026
- SUSE-SU-2026:24235-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 21, 2026
- SUSE-SU-2026:24197-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 21, 2026
- ALAS2023-2026-3196 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 21, 2026
- SUSE-SU-2026:24184-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 20, 2026
- SUSE-SU-2026:24179-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 20, 2026
- openSUSE-SU-2026:22091-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Oct 19, 2026
- RHSA-2026:77690 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 19, 2026
- RHSA-2026:77689 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 17, 2026
- ALAS2023-2026-3187 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 12, 2026
- RLSA-2026:77689 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Oct 9, 2026
- RLSA-2026:77690 Important: kernel security, bug fix, and enhancement update Rocky Linux Security Advisories · Oct 9, 2026
- ELSA-2026-77690 Important: kernel security, bug fix, and enhancement update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Oct 8, 2026
- ELSA-2026-77689 Important: kernel security, bug fix, and enhancement update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 8, 2026
- ELSA-2026-500374 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 7, 2026
- openSUSE-SU-2026:11805-1 kernel-devel-7.2.6-1.1 on GA media SUSE / openSUSE Security Updates · Sep 18, 2026