Description
The ext4_fill_super function in fs/ext4/super.c in the Linux kernel through 4.15.15 does not always initialize the crc32c checksum driver, which allows attackers to cause a denial of service (ext4_xattr_inode_hash NULL pointer dereference and system crash) via a crafted ext4 image.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | Linux kernel through version 4.15 | Linux kernel through version 4.15 | — |
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 | 4.15.17-1 | — |
| Debian 13 | linux | 4.15.17-1 | — |
| Debian 12 | linux | 4.15.17-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux | 4.15.0-24.26 | USN-3695-1 |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1011.11 | USN-3695-1 |
| Ubuntu 18.04 LTS | linux-azure | 4.15.0-1014.14 | USN-3695-1 |
| Ubuntu 18.04 LTS | linux-gcp | 4.15.0-1010.10 | USN-3695-1 |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1012.12 | USN-3695-1 |
| Ubuntu 18.04 LTS | linux-oem | 4.15.0-1009.12 | USN-3695-1 |
| Ubuntu 18.04 LTS | linux-raspi2 | 4.15.0-1013.14 | USN-3695-1 |
| Ubuntu 16.04 LTS | linux-gcp +1 | 4.15.0-1014.14~16.04.1 | USN-3695-2 |
| Ubuntu 16.04 LTS | linux-hwe | 4.15.0-24.26~16.04.1 | USN-3695-2 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | kernel-alt +1 | 4.14.0-115.el7a | RHSA-2018:2948 |
| RHEL 7 | kernel-rt +10 | 3.10.0-957.rt56.910.el7 | RHSA-2018:3096 |
| RHEL 7 | perf +18 | 3.10.0-957.el7 | RHSA-2018:3083, RHSA-2018:2948 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | kernel-docs +6 | 4.12.14-25.3.1 | SUSE-SU-2018:2092-1 |
| SLES 12 SP2 | kernel-syms +2 | 4.4.121-92.85.1 | SUSE-SU-2018:1855-2, SUSE-SU-2018:1855-1 |
| SLES 12 SP2 | kgraft-patch-SLE12-SP2_Update_23 | 1-3.5.1 | SUSE-SU-2018:1855-2, SUSE-SU-2018:1855-1 |
| SLES 12 SP1 | kernel-xen +3 | 3.12.74-60.64.96.1 | SUSE-SU-2018:1761-1 |
| SLES 12 SP1 | kgraft-patch-SLE12-SP1_Update_29 | 1-2.3.1 | SUSE-SU-2018:1761-1 |
| SLES 12 | kernel-ec2 +4 | 3.12.61-52.136.1 | SUSE-SU-2018:1762-1, SUSE-SU-2018:1761-1 |
| SLES 12 | kgraft-patch-SLE12_Update_36 | 1-1.3.1 | SUSE-SU-2018:1762-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP2 | kernel-syms +2 | 4.4.121-92.85.1 | SUSE-SU-2018:1855-1 |
| SLES for SAP 12 SP2 | kgraft-patch-SLE12-SP2_Update_23 | 1-3.5.1 | SUSE-SU-2018:1855-1 |
| SLES for SAP 12 SP1 | kernel-xen +3 | 3.12.74-60.64.96.1 | SUSE-SU-2018:1761-1 |
| SLES for SAP 12 SP1 | kgraft-patch-SLE12-SP1_Update_29 | 1-2.3.1 | SUSE-SU-2018:1761-1 |
| SLE Real Time 12 SP3 | kernel-rt +3 | 4.4.138-3.14.1 | SUSE-SU-2018:1816-1 |
| SLE Live Patching 15 | kernel-default | 4.12.14-25.3.1 | SUSE-SU-2018:2092-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_1 | 1-1.3.1 | SUSE-SU-2018:2092-1 |
| SUSE OpenStack Cloud 7 | kernel-syms +2 | 4.4.121-92.85.1 | SUSE-SU-2018:1855-1 |
| SUSE OpenStack Cloud 7 | kgraft-patch-SLE12-SP2_Update_23 | 1-3.5.1 | SUSE-SU-2018:1855-1 |
| SUSE Enterprise Storage 4 | kernel-syms +2 | 4.4.121-92.85.1 | SUSE-SU-2018:1855-1 |
| SUSE Enterprise Storage 4 | kgraft-patch-SLE12-SP2_Update_23 | 1-3.5.1 | SUSE-SU-2018:1855-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | dtrace-modules-3.8.13-118.30.1.el6uek | 0.4.5-3.el6 | ELSA-2019-4532 |
| Oracle Linux 7 | dtrace-modules-3.8.13-118.30.1.el7uek | 0.4.5-3.el7 | ELSA-2019-4532 |
| Oracle Linux 7 | kernel-uek +5 | 3.8.13-118.30.1.el7uek | ELSA-2019-4532, ELSA-2019-4510 |
| Oracle Linux 7 | perf +12 | 3.10.0-957.el7 | ELSA-2018-3083 |
Advisories 14
- RHSA-2018:3083 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jul 8, 2026
- RHSA-2018:3096 Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jul 8, 2026
- RHSA-2018:2948 Red Hat Security Advisory: kernel-alt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jul 1, 2026
- USN-3695-1 linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oem, linux-raspi2 vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-3695-2 linux-hwe, linux-azure vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2018:1855-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2092-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1762-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1855-2 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1816-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
- SUSE-SU-2018:1761-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2019-4532 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Feb 6, 2019
- ELSA-2019-4510 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jan 15, 2019
- ELSA-2018-3083 Important: kernel security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Nov 5, 2018
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1560788
- RHSA-2018:3083 vendor-advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git/commit/?id=18db4b4e6fc31eda838dd1c1296d67dbcb3dc957
- http://openwall.com/lists/oss-security/2018/03/29/1
- USN-3695-1 vendor-advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git/commit/?id=a45403b51582a87872927a3e0fc0a389c26867f1
- USN-3695-2 vendor-advisory
- https://bugzilla.kernel.org/show_bug.cgi?id=199183
- RHSA-2018:2948 vendor-advisory
- RHSA-2018:3096 vendor-advisory