Description
A flaw was found in the Linux kernel's NFS implementation, all versions 3.x and all versions 4.x up to 4.20. An attacker, who is able to mount an exported NFS filesystem, is able to trigger a null pointer dereference by using an invalid NFS sequence. This can panic the machine and deny access to the NFS server. Any outstanding disk writes to the NFS server will be lost.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | kernel: | all 3.x, all 4.x up to 4.20 | — |
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 | 4.18.20-1 | — |
| Debian 13 | linux | 4.18.20-1 | — |
| Debian 12 | linux | 4.18.20-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +3 | No fix yet | — |
| Ubuntu 18.04 LTS | linux | 4.15.0-46.49 | — |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1033.35 | — |
| Ubuntu 18.04 LTS | linux-azure | 4.18.0-1011.11~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-gcp | 4.15.0-1028.29 | — |
| Ubuntu 18.04 LTS | linux-gcp-edge | 4.18.0-1006.7~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-hwe | 4.18.0-14.15~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1030.30 | — |
| Ubuntu 18.04 LTS | linux-oem | 4.15.0-1034.39 | — |
| Ubuntu 18.04 LTS | linux-oracle | 4.15.0-1009.11 | — |
| Ubuntu 18.04 LTS | linux-raspi2 | 4.15.0-1032.34 | — |
| Ubuntu 16.04 LTS | linux-aws-hwe | 4.15.0-1033.35~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-azure | 4.15.0-1040.44 | — |
| Ubuntu 16.04 LTS | linux-gcp | 4.15.0-1028.29~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-hwe | 4.15.0-46.49~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-oracle | 4.15.0-1009.11~16.04.1 | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | linux-azure | 4.15.0-1040.44~14.04.1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | kernel-rt +12 | 4.18.0-193.rt13.51.el8 | RHSA-2020:1567 |
| RHEL 8 | perf +26 | 4.18.0-193.el8 | RHSA-2020:1769 |
| RHEL 7 | kernel-alt | 4.14.0-115.18.1.el7a | RHSA-2020:0740 |
| RHEL 7 | kernel-rt +10 | 3.10.0-957.27.2.rt56.940.el7 | RHSA-2019:1891 |
| RHEL 7 | perf +19 | 3.10.0-957.27.2.el7 | RHSA-2020:0740, RHSA-2019:1873 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7.4 EUS | perf +17 | 3.10.0-693.58.1.el7 | RHSA-2019:2696 |
| Red Hat MRG 2 | kernel-rt +10 | 1:3.10.0-693.58.1.rt56.652.el6rt | RHSA-2019:2730 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | kernel-azure +2 | 4.12.14-8.13.1 | SUSE-SU-2019:2069-1 |
| SLES 15 SP1 | kernel-docs +5 | 4.12.14-197.7.1 | SUSE-SU-2019:1744-1 |
| SLES 15 | kernel-azure +2 | 4.12.14-5.33.1 | SUSE-SU-2019:1829-1 |
| SLES 15 | kernel-docs +6 | 4.12.14-150.27.1 | SUSE-SU-2019:1855-1 |
| SLES 12 SP4 | kernel-docs +4 | 4.12.14-95.24.1 | SUSE-SU-2019:1851-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP4 | kernel-syms +2 | 4.12.14-95.24.1 | SUSE-SU-2019:1851-1 |
| SLE Real Time 12 SP4 | kernel-rt +3 | 4.12.14-8.3.1 | SUSE-SU-2019:2450-1 |
| SLE Live Patching 15 SP1 | kernel-default | 4.12.14-197.7.1 | SUSE-SU-2019:1744-1 |
| SLE Live Patching 15 SP1 | kernel-livepatch-SLE15-SP1_Update_2 | 1-3.3.1 | SUSE-SU-2019:1744-1 |
| SLE Live Patching 15 | kernel-default | 4.12.14-150.27.1 | SUSE-SU-2019:1855-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_12 | 1-1.5.1 | SUSE-SU-2019:1855-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_8 | 7-2.3 | SUSE-SU-2019:3246-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_0 | 9-2.25.1 | SUSE-SU-2019:3252-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_1 | 8-2.5 | SUSE-SU-2019:3252-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_2 | 7-2.5 | SUSE-SU-2019:3223-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_6 | 1-6.5.1 | SUSE-SU-2019:1851-1 |
| SUSE Real Time Module 15 SP1 | kernel-rt +3 | 4.12.14-14.8.1 | SUSE-SU-2019:2430-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | kernel-docs +8 | 4.12.14-lp151.28.10.1 | openSUSE-SU-2019:1757-1 |
| openSUSE Leap 15.0 | kernel-docs +8 | 4.12.14-lp150.12.67.1 | openSUSE-SU-2019:1716-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | perf +19 | 4.18.0-193.el8 | ELSA-2020-1769 |
| Oracle Linux 7 | kernel-uek +8 | 4.14.35-1902.4.8.el7uek | ELSA-2019-4746 |
| Oracle Linux 7 | perf +12 | 3.10.0-957.27.2.el7 | ELSA-2019-4746, ELSA-2019-1873 |
Advisories 22
- RHSA-2020:1769 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2020:1567 Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Aug 7, 2026
- RHSA-2019:2730 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2019:2696 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2020:0740 Red Hat Security Advisory: kernel-alt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2019:1891 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2019:1873 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- SUSE-SU-2019:1855-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:1851-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3252-1 Security update for the Linux Kernel (Live Patch 1 for SLE 12 SP4) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2450-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:1829-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:1757-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3246-1 Security update for the Linux Kernel (Live Patch 8 for SLE 15) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2069-1 Security update for the Linux Kernel for Azure SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:1744-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2430-1 Security update for kernel-source-rt SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3223-1 Security update for the Linux Kernel (Live Patch 2 for SLE 12 SP4) SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:1716-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2020-1769 Important: kernel security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 5, 2020
- ELSA-2019-4746 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Aug 15, 2019
- ELSA-2019-1873 Important: kernel security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jul 30, 2019
References
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16871
- RHSA-2019:2696 vendor-advisory
- RHSA-2019:2730 vendor-advisory
- https://support.f5.com/csp/article/K18657134
- https://support.f5.com/csp/article/K18657134?utm_source=f5support&%3Butm_medium=RSS
- RHSA-2020:0740 vendor-advisory
- https://security.netapp.com/advisory/ntap-20211004-0002/