Description
fs/nfs/nfs4client.c in the Linux kernel before 5.13.4 has incorrect connection-setup ordering, which allows operators of remote NFSv4 servers to cause a denial of service (hanging of mounts) by arranging for those servers to be unreachable during trunking detection.
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 | 5.14.6-1 | — |
| Debian 13 | linux | 5.14.6-1 | — |
| Debian 12 | linux | 5.14.6-1 | — |
| Debian 11 | linux | 5.10.46-5 | DSA-4978-1 |
| Debian 9 | linux | 4.9.290-1 | DLA-2843-1 |
| Debian 9 | linux-4.19 | 4.19.208-1~deb9u1 | DLA-2785-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu 20.04 LTS | linux | 5.4.0-88.99 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-aws | 5.4.0-1057.60 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-aws-5.11 +1 | 5.11.0-1019.20~20.04.1 | USN-5092-2, USN-5092-1 |
| Ubuntu 20.04 LTS | linux-azure | 5.4.0-1059.62 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-azure-5.11 | 5.11.0-1017.18~20.04.1 | USN-5092-2 |
| Ubuntu 20.04 LTS | linux-azure-5.8 | 5.8.0-1043.46~20.04.1 | USN-5120-1 |
| Ubuntu 20.04 LTS | linux-bluefield | 5.4.0-1019.22 | — |
| Ubuntu 20.04 LTS | linux-gcp | 5.4.0-1053.57 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-gcp-5.11 | 5.11.0-1020.22~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-gke | 5.4.0-1053.56 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-gkeop | 5.4.0-1024.25 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-hwe-5.11 | 5.11.0-37.41~20.04.2 | USN-5092-2 |
| Ubuntu 20.04 LTS | linux-ibm | 5.4.0-1005.6 | — |
| Ubuntu 20.04 LTS | linux-kvm | 5.4.0-1047.49 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-oem-5.10 | 5.10.0-1049.51 | USN-5106-1 |
| Ubuntu 20.04 LTS | linux-oem-5.13 | 5.13.0-1014.18 | USN-5096-1 |
| Ubuntu 20.04 LTS | linux-oracle | 5.4.0-1055.59 | USN-5091-1 |
| Ubuntu 20.04 LTS | linux-raspi | 5.4.0-1044.48 | USN-5091-2 |
| Ubuntu 20.04 LTS | linux-riscv +7 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-riscv-5.11 | 5.11.0-1020.21~20.04.1 | — |
| Ubuntu 18.04 LTS | linux | 4.15.0-162.170 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1115.122 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-aws-5.4 | 5.4.0-1057.60~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-azure-4.15 | 4.15.0-1126.139 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-azure-5.4 | 5.4.0-1059.62~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-dell300x | 4.15.0-1030.35 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-gcp +13 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp-4.15 | 4.15.0-1111.125 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-gcp-5.4 | 5.4.0-1053.57~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-gke-5.4 | 5.4.0-1053.56~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-gkeop-5.4 | 5.4.0-1024.25~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-hwe-5.4 | 5.4.0-87.98~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1102.104 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-oracle | 4.15.0-1083.91 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-oracle-5.4 | 5.4.0-1055.59~18.04.1 | USN-5091-1 |
| Ubuntu 18.04 LTS | linux-raspi-5.4 | 5.4.0-1044.48~18.04.1 | USN-5091-2 |
| Ubuntu 18.04 LTS | linux-raspi2 | 4.15.0-1098.104 | USN-5136-1 |
| Ubuntu 18.04 LTS | linux-snapdragon | 4.15.0-1115.124 | USN-5136-1 |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro FIPS 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-aws-fips | 5.4.0-1069.73+fips2 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-azure-fips | 5.4.0-1073.76+fips1 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips | 5.4.0-1034.40 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-gcp-fips | 5.4.0-1067.71~20.04.1 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-aws-fips | 4.15.0-2056.58 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-azure-fips | 4.15.0-2038.42 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips | 4.15.0-1072.81 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-gcp-fips | 4.15.0-2021.23 | — |
| Ubuntu Pro 16.04 LTS | linux-aws-hwe | 4.15.0-1115.122~16.04.1 | USN-5136-1 |
| Ubuntu Pro 16.04 LTS | linux-azure | 4.15.0-1126.139~16.04.1 | USN-5136-1 |
| Ubuntu Pro 16.04 LTS | linux-gcp | 4.15.0-1111.125~16.04.1 | USN-5136-1 |
| Ubuntu Pro 16.04 LTS | linux-hwe | 4.15.0-162.170~16.04.1 | USN-5136-1 |
| Ubuntu Pro 16.04 LTS | linux-oracle | 4.15.0-1083.91~16.04.1 | USN-5136-1 |
| Ubuntu Pro 14.04 LTS | linux-azure | 4.15.0-1126.139~14.04.1 | USN-5136-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | kernel-livepatch-4.14.268-205.500 | 1.0-0.amzn2 | ALAS2-2022-1761 |
| Amazon Linux 2 | perf +8 | 4.14.268-205.500.amzn2 | ALAS2-2022-1761 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | kernel | 5.10.78.1-1 | — |
Advisories 12
- USN-5136-1 linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-dell300x, linux-gcp, linux-gcp-4.15, linux-hwe, linux-kvm, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities Ubuntu Security Notices (USN) · Sep 14, 2026
- USN-5120-1 linux-azure-5.8 vulnerabilities Ubuntu Security Notices (USN) · Sep 14, 2026
- USN-5096-1 linux-oem-5.13 vulnerabilities Ubuntu Security Notices (USN) · Sep 9, 2026
- USN-5092-1 linux, linux-aws, linux-aws-5.11, linux-gcp, linux-kvm, linux-oracle, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-5106-1 linux-oem-5.10 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-5092-2 linux-hwe-5.11, linux-azure, linux-azure-5.11, linux-oracle-5.11 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-5091-1 linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp, linux-gcp-5.4, linux-gke, linux-gke-5.4, linux-gkeop, linux-gkeop-5.4, linux-hwe-5.4, linux-kvm, linux-oracle, linux-oracle-5.4 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-5091-2 linux-raspi, linux-raspi-5.4 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- DSA-4978-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2843-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2785-1 linux-4.19 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- ALAS2-2022-1761 Important: kernel security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Oct 2, 2025
References
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4
- https://github.com/torvalds/linux/commit/dd99e9f98fbf423ff6d365b37a98e8879170f17c
- https://security.netapp.com/advisory/ntap-20210902-0010/
- DSA-4978 vendor-advisory
- [debian-lts-announce] 20211015 [SECURITY] [DLA 2785-1] linux-4.19 security update mailing-list
- [debian-lts-announce] 20211216 [SECURITY] [DLA 2843-1] linux security update mailing-list