Description
net/sunrpc/xdr.c in the Linux kernel before 5.13.4 allows remote attackers to cause a denial of service (xdr_set_page_base slab-out-of-bounds access) by performing many NFS 4.2 READ_PLUS operations.
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.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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-5.11 | 5.11.0-1017.18~20.04.1 | USN-5092-2 |
| Ubuntu 20.04 LTS | linux-gcp-5.11 | 5.11.0-1020.22~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-hwe-5.11 | 5.11.0-37.41~20.04.2 | USN-5092-2 |
| Ubuntu 20.04 LTS | linux-oem-5.13 | 5.13.0-1014.18 | USN-5096-1 |
| Ubuntu 20.04 LTS | linux-riscv +6 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-riscv-5.11 | 5.11.0-1020.21~20.04.1 | — |
| Ubuntu 18.04 LTS | linux-gcp +13 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | kernel-rt +12 | 4.18.0-305.17.1.rt7.89.el8_4 | RHSA-2021:3440 |
| RHEL 8 | perf +26 | 4.18.0-305.17.1.el8_4 | RHSA-2021:3447 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | kernel-tools-libs-devel | 4.18.0-305.17.1.el8_4 | ALSA-2021:3447 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | kernel | 4.18.0-305.17.1.el8_4 | RLSA-2021:3447 |
| Rocky Linux 8 | kernel-rt | 4.18.0-305.17.1.rt7.89.el8_4 | RLSA-2021:3440 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | kernel | 5.10.78.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | perf +19 | 4.18.0-305.17.1.el8_4 | ELSA-2021-3447 |
Advisories 10
- ALSA-2021:3447 Important: kernel security and bug fix update AlmaLinux Security Advisories · Oct 29, 2026
- USN-5096-1 linux-oem-5.13 vulnerabilities Ubuntu Security Notices (USN) · Sep 9, 2026
- RHSA-2021:3447 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Aug 26, 2026
- RHSA-2021:3440 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 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-5092-2 linux-hwe-5.11, linux-azure, linux-azure-5.11, linux-oracle-5.11 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- RLSA-2021:3447 Important: kernel security and bug fix update Rocky Linux Security Advisories · Feb 5, 2026
- RLSA-2021:3440 Moderate: kernel-rt security and bug fix update Rocky Linux Security Advisories · Feb 5, 2026
- WID-SEC-2022-0515 IBM Spectrum Protect: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jun 8, 2023
- ELSA-2021-3447 Important: kernel security and bug fix update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Sep 8, 2021