Description
In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the same socket file descriptor, related to the sock_close and sockfs_setattr functions. fchownat does not increment the file descriptor reference count, which allows close to set the socket to NULL during fchownat's execution, leading to a NULL pointer dereference and system crash.
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 | 4.17.3-1 | — |
| Debian 13 | linux | 4.17.3-1 | — |
| Debian 12 | linux | 4.17.3-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux | 4.15.0-33.36 | USN-3752-1 |
| Ubuntu 18.04 LTS | linux-aws +1 | 4.15.0-1020.20 | USN-3752-1 |
| Ubuntu 18.04 LTS | linux-azure | 4.15.0-1022.23 | USN-3752-3 |
| Ubuntu 18.04 LTS | linux-gcp | 4.15.0-1018.19 | USN-3752-1 |
| Ubuntu 18.04 LTS | linux-oem | 4.15.0-1017.20 | USN-3752-3 |
| Ubuntu 18.04 LTS | linux-raspi2 | 4.15.0-1021.23 | USN-3752-1 |
| Ubuntu 16.04 LTS | linux-azure | 4.15.0-1022.22~16.04.1 | USN-3752-3 |
| Ubuntu 16.04 LTS | linux-gcp | 4.15.0-1018.19~16.04.2 | USN-3752-3 |
| Ubuntu 16.04 LTS | linux-hwe | 4.15.0-33.36~16.04.1 | USN-3752-2 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | perf +14 | 4.14.0-115.el7a | RHSA-2018:2948 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | kernel-azure +2 | 4.12.14-5.19.1 | SUSE-SU-2019:0150-1 |
| SLES 15 | kernel-docs +6 | 4.12.14-25.28.1 | SUSE-SU-2019:0224-1 |
| SLES 12 SP4 | kernel-azure +2 | 4.12.14-6.6.2 | SUSE-SU-2019:0222-1 |
| SLES 12 SP4 | kernel-docs +4 | 4.12.14-95.6.1 | SUSE-SU-2019:0196-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP4 | kernel-azure +2 | 4.12.14-6.6.2 | SUSE-SU-2019:0222-1 |
| SLES for SAP 12 SP4 | kernel-syms +2 | 4.12.14-95.6.1 | SUSE-SU-2019:0196-1 |
| SLE Live Patching 15 | kernel-default | 4.12.14-25.28.1 | SUSE-SU-2019:0224-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_0 | 9-25.2 | SUSE-SU-2019:0740-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_1 | 8-2.1 | SUSE-SU-2019:0740-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_8 | 1-1.3.1 | SUSE-SU-2019:0224-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_2 | 1-6.3.1 | SUSE-SU-2019:0196-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 5.14.6-1.4 | openSUSE-SU-2024:13704-1, openSUSE-SU-2024:10728-1 |
| openSUSE Leap 15.0 | kernel-source | 4.12.14-lp150.12.45.1 | openSUSE-SU-2019:0065-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | perf +7 | 4.14.51-66.38.amzn2 | ALAS2-2018-1044 |
Advisories 13
- RHSA-2018:2948 Red Hat Security Advisory: kernel-alt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jul 1, 2026
- USN-3752-1 linux, linux-aws, linux-gcp, linux-kvm, linux-raspi2 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-3752-3 linux-azure, linux-oem, linux-gcp vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-3752-2 linux-hwe vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- SUSE-SU-2019:0222-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0150-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0224-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:13704-1 kernel-devel-longterm-6.6.17-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0196-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0740-1 Security update for the Linux Kernel (Live Patch 1 for SLE 15) SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10728-1 kernel-devel-5.14.6-1.4 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:0065-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
- ALAS2-2018-1044 Moderate: kernel security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jul 5, 2018
References
- USN-3752-2 vendor-advisory
- USN-3752-3 vendor-advisory
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6d8c50dcb029872b298eea68cc6209c866fd3e14
- https://patchwork.ozlabs.org/patch/926519/
- RHSA-2018:2948 vendor-advisory
- https://lkml.org/lkml/2018/6/5/14
- 104453 vdb-entry
- USN-3752-1 vendor-advisory
- https://github.com/torvalds/linux/commit/6d8c50dcb029872b298eea68cc6209c866fd3e14