Out-of-bounds read in Linux kernel - CVE-2026-53040

 

Out-of-bounds read in Linux kernel - CVE-2026-53040

Published: June 25, 2026


Vulnerability identifier: #VU135317
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-53040
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to an out-of-bounds read in the ocfs2 freefrag scan logic in fs/ocfs2/ioctl.c when processing a crafted filesystem through OCFS2_IOC_INFO with OCFS2_INFO_FL_NON_COHERENT. A local user can supply a crafted filesystem and issue the ioctl request to cause a denial of service.

The issue occurs in the non-coherent scan path, which reads raw group descriptor blocks without the validation performed by the coherent path.


Affected software

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Micro
SUSE Linux Micro Extras
SUSE Linux Enterprise Live Patching
Legacy Module
SUSE Real Time Module
Basesystem Module
Development Tools Module
Public Cloud Module
Ubuntu
openEuler
kgraft-patch-4_12_14-122_320-default
kernel-livepatch-6_4_0-150700_7_62-rt-debuginfo
kernel-livepatch-SLE15-SP7-RT_Update_17-debugsource
kernel-livepatch-6_4_0-150700_7_62-rt
kernel-livepatch-6_4_0-150700_53_66-default-debuginfo
kernel-livepatch-6_4_0-150700_53_66-default
kernel-livepatch-SLE15-SP7_Update_18-debugsource
ocfs2-kmp-default-debuginfo
kernel-source
gfs2-kmp-default
ocfs2-kmp-default
dlm-kmp-default-debuginfo
kernel-default-debuginfo
dlm-kmp-default
cluster-md-kmp-default-debuginfo
kernel-default-base-debuginfo
kernel-default-debugsource
kernel-default-base
kernel-default-devel
kernel-default-kgraft-devel
kernel-default-kgraft
kernel-default-man
kernel-devel
kernel-macros
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
kernel-default
kernel-default-devel-debuginfo
kernel-syms
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (Ubuntu package)
kernel-rt-debugsource
kernel-default-livepatch
kernel-kvmsmall
kernel-rt-devel-debuginfo
kernel-rt-devel
kernel-rt
kernel-rt-livepatch
kernel-rt-debuginfo
kernel-source-rt
kernel-devel-rt
kernel-kvmsmall-debugsource
kernel-64kb-debugsource
kernel-64kb-devel
kernel-obs-build
kernel-obs-build-debugsource
kernel-64kb
kernel-kvmsmall-debuginfo
cluster-md-kmp-rt
gfs2-kmp-rt-debuginfo
dlm-kmp-rt
kernel-syms-rt
ocfs2-kmp-rt-debuginfo
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
ocfs2-kmp-rt
gfs2-kmp-rt
kernel-azure-debugsource
kernel-azure
kernel-azure-devel-debuginfo
kernel-default-extra
kernel-default-extra-debuginfo
kernel-azure-devel
kernel-azure-debuginfo
reiserfs-kmp-default-debuginfo
kernel-default-livepatch-devel
kernel-64kb-debuginfo
kernel-zfcpdump
kernel-64kb-devel-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
reiserfs-kmp-default
kernel-docs
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

How to mitigate CVE-2026-53040

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kgraft-patch-4_12_14-122_320-default - update to 1-8.3.1
kernel-livepatch-6_4_0-150700_7_62-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-SLE15-SP7-RT_Update_17-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_62-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_66-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_66-default - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_18-debugsource - update to 1-150700.15.3.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
kernel-source - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
gfs2-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
ocfs2-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
dlm-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
kernel-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
dlm-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
kernel-default-base-debuginfo - update to 4.12.14-122.320.1
kernel-default-debugsource - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-base - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1.150700.17.39.1
kernel-default-devel - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-kgraft-devel - update to 4.12.14-122.320.1
kernel-default-kgraft - update to 4.12.14-122.320.1
kernel-default-man - update to 4.12.14-122.320.1
kernel-devel - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-macros - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
cluster-md-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
gfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.66.1
kernel-default - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-syms - addressed in versions 4.12.14-122.320.1, 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-devel - update to 5.10.0-325.0.0.226
python3-perf-debuginfo - update to 5.10.0-325.0.0.226
python3-perf - update to 5.10.0-325.0.0.226
perf-debuginfo - update to 5.10.0-325.0.0.226
perf - update to 5.10.0-325.0.0.226
kernel-tools-devel - update to 5.10.0-325.0.0.226
kernel-tools-debuginfo - update to 5.10.0-325.0.0.226
kernel-tools - update to 5.10.0-325.0.0.226
kernel-source - update to 5.10.0-325.0.0.226
kernel-headers - update to 5.10.0-325.0.0.226
kernel-debugsource - update to 5.10.0-325.0.0.226
kernel-debuginfo - update to 5.10.0-325.0.0.226
bpftool-debuginfo - update to 5.10.0-325.0.0.226
bpftool - update to 5.10.0-325.0.0.226
kernel - update to 5.10.0-325.0.0.226
linux (Ubuntu package) - addressed in versions 5.15.0.184.155, 5.15.0-184.194, 5.15.0-184.194~20.04.1, 5.15.0.186.166, 5.15.0-186.196, 5.15.0-186.196~20.04.1, 5.15.0.1075.78, 5.15.0-1075.79, 5.15.0.1095.94, 5.15.0-1095.103, 5.15.0.1104.100, 5.15.0-1104.109, 5.15.0.1108.107, 5.15.0-1108.114, 5.15.0.1111.115, 5.15.0-1111.120+fips1, 5.15.0.1112.102, 5.15.0.1112.109, 5.15.0-1112.122, 5.15.0-1112.122+fips1, 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2, 7.0.0-28.28, 7.0.0-28.28.1, 7.0.0-1003.4, 7.0.0-1008.8
linux-aws (Ubuntu package) - addressed in versions 5.15.0.186.109, 5.15.0-186.196+fips1, 5.15.0.1106.103, 5.15.0-1106.110, 5.15.0.1107.107, 5.15.0-1107.108, 5.15.0.1112.108, 5.15.0.1112.115, 5.15.0-1112.119, 5.15.0-1112.119+fips1, 5.15.0-1112.119~20.04.1, 6.8.0-1061.64+1, 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1053.53, 5.15.0.1053.55, 5.15.0.1064.64, 5.15.0-1064.66
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1064.66~20.04.1
linux-intel-iot-realtime (Ubuntu package) - addressed in versions 5.15.0-1104.106, 5.15.0.1104.108, 5.15.0-1107.113~20.04.1
linux-intel-iotg (Ubuntu package) - addressed in versions 5.15.0.1107.106, 5.15.0-1107.113
linux-azure (Ubuntu package) - addressed in versions 5.15.0.1109.105, 5.15.0-1109.115, 5.15.0.1117.115, 5.15.0-1117.126, 6.8.0-1063.71, 6.8.0-1063.71~22.04.1, 7.0.0-1009.9, 7.0.0-1010.10
linux-azure-5.15 (Ubuntu package) - addressed in versions 5.15.0-1109.115~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2
linux-azure-fips (Ubuntu package) - addressed in versions 5.15.0.1117.102, 5.15.0-1117.126+fips1, 6.8.0-1063.71+fips2
linux-azure-fde (Ubuntu package) - addressed in versions 5.15.0-1117.126, 6.8.0-1062.69
kernel-rt-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-default-livepatch - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-kvmsmall - update to 6.4.0-49.1
kernel-rt-devel-debuginfo - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-rt-devel - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-rt - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-rt-livepatch - update to 6.4.0-49.1
kernel-rt-debuginfo - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-source-rt - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-devel-rt - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-kvmsmall-debugsource - update to 6.4.0-49.1
kernel-64kb-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-64kb-devel - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-obs-build - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-64kb - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-kvmsmall-debuginfo - update to 6.4.0-49.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.62.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
dlm-kmp-rt - update to 6.4.0-150700.7.62.1
kernel-syms-rt - update to 6.4.0-150700.7.62.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.62.1
gfs2-kmp-rt - update to 6.4.0-150700.7.62.1
kernel-azure-debugsource - update to 6.4.0-150700.53.66.1
kernel-azure - update to 6.4.0-150700.53.66.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.66.1
kernel-default-extra - update to 6.4.0-150700.53.66.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.66.1
kernel-azure-devel - update to 6.4.0-150700.53.66.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.66.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.66.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.66.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.66.1
kernel-zfcpdump - update to 6.4.0-150700.53.66.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.66.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.66.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.66.1
reiserfs-kmp-default - update to 6.4.0-150700.53.66.1
kernel-docs - update to 6.4.0-150700.53.66.2
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1, 7.0.0-1008.8, 7.0.0-1010.10
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1009.9

External References

Related Security Bulletins