Out-of-bounds read in Linux kernel - CVE-2026-89778

Vulnerability identifier: #VU150504

CSH Severity: High

CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-89778

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to read memory out of bounds.

The vulnerability exists due to an out-of-bounds read in zisofs_fill_pages() when reading a compressed file on a mounted ISO9660 image containing a crafted ZF Rock Ridge record. A remote attacker can provide a crafted ISO9660 image to read memory out of bounds.

The issue is triggered when an empty zisofs block follows a sub-page block with a nonzero page offset.

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
SUSE Real Time Module
Ubuntu
openEuler
linux-nvidia-tegra-igx (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux (Ubuntu package)
linux-oracle (Ubuntu package)
linux-gcp (Ubuntu package)
linux-aws (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
kgraft-patch-4_12_14-122_336-default
kernel-livepatch-SLE15-SP7-RT_Update_22-debugsource
kernel-livepatch-6_4_0-150700_7_81-rt
kernel-livepatch-6_4_0-150700_7_81-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_87-default
kernel-livepatch-SLE15-SP7_Update_23-debugsource
kernel-livepatch-6_4_0-150700_53_87-default-debuginfo
kernel-macros
kernel-source
kernel-devel
kernel-default-devel-debuginfo
dlm-kmp-default
kernel-default-devel
gfs2-kmp-default
ocfs2-kmp-default
dlm-kmp-default-debuginfo
kernel-default-base
kernel-default-man
gfs2-kmp-default-debuginfo
cluster-md-kmp-default
cluster-md-kmp-default-debuginfo
kernel-syms
ocfs2-kmp-default-debuginfo
kernel-default-base-debuginfo
kernel-default-debuginfo
kernel-default-kgraft-devel
kernel-default-kgraft
kernel-default-debugsource
kernel-default
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-headers
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
python3-perf-debuginfo
dlm-kmp-rt-debuginfo
gfs2-kmp-rt-debuginfo
kernel-devel-rt
kernel-syms-rt
kernel-rt-devel
kernel-source-rt
kernel-rt
cluster-md-kmp-rt
kernel-rt-debuginfo
ocfs2-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-rt-devel-debuginfo
dlm-kmp-rt
kernel-rt-debugsource
ocfs2-kmp-rt
gfs2-kmp-rt
kernel-obs-build
kernel-obs-build-debugsource
kernel-azure
kernel-azure-debugsource
kernel-64kb-devel-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-devel
kernel-default-extra
kernel-default-extra-debuginfo
kernel-default-livepatch-devel
kernel-zfcpdump
kernel-default-livepatch
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
kernel-docs
kernel-64kb-debugsource
kernel-64kb-debuginfo
kernel-64kb-devel
kernel-64kb
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
linux (Debian package)

Install security update from vendor's repository.

linux-nvidia-tegra-igx (Ubuntu package) - update to 5.15.0-1059.59
linux-nvidia-tegra (Ubuntu package) - update to 5.15.0-1070.72
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1070.72~20.04.1
linux-azure-fde (Ubuntu package) - update to 5.15.0-1124.133
linux (Ubuntu package) - update to 7.0.0-42.42
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
kgraft-patch-4_12_14-122_336-default - update to 1-8.3.1
kernel-livepatch-SLE15-SP7-RT_Update_22-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_81-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_81-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_87-default - update to 1-150700.15.3.2
kernel-livepatch-SLE15-SP7_Update_23-debugsource - update to 1-150700.15.3.2
kernel-livepatch-6_4_0-150700_53_87-default-debuginfo - update to 1-150700.15.3.2
kernel-macros - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-source - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-devel - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
dlm-kmp-default - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-default-devel - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
gfs2-kmp-default - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
ocfs2-kmp-default - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
dlm-kmp-default-debuginfo - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-default-base - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3.150700.17.49.2
kernel-default-man - update to 4.12.14-122.336.1
gfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
cluster-md-kmp-default - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-syms - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-default-base-debuginfo - update to 4.12.14-122.336.1
kernel-default-debuginfo - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-default-kgraft-devel - update to 4.12.14-122.336.1
kernel-default-kgraft - update to 4.12.14-122.336.1
kernel-default-debugsource - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel-default - addressed in versions 4.12.14-122.336.1, 6.4.0-150700.53.87.3
kernel - update to 5.10.0-337.0.0.238
bpftool - update to 5.10.0-337.0.0.238
bpftool-debuginfo - update to 5.10.0-337.0.0.238
kernel-debuginfo - update to 5.10.0-337.0.0.238
kernel-debugsource - update to 5.10.0-337.0.0.238
kernel-devel - update to 5.10.0-337.0.0.238
kernel-headers - update to 5.10.0-337.0.0.238
kernel-source - update to 5.10.0-337.0.0.238
kernel-tools - update to 5.10.0-337.0.0.238
kernel-tools-debuginfo - update to 5.10.0-337.0.0.238
kernel-tools-devel - update to 5.10.0-337.0.0.238
perf - update to 5.10.0-337.0.0.238
perf-debuginfo - update to 5.10.0-337.0.0.238
python3-perf - update to 5.10.0-337.0.0.238
python3-perf-debuginfo - update to 5.10.0-337.0.0.238
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.81.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.81.1
kernel-devel-rt - update to 6.4.0-150700.7.81.1
kernel-syms-rt - update to 6.4.0-150700.7.81.1
kernel-rt-devel - update to 6.4.0-150700.7.81.1
kernel-source-rt - update to 6.4.0-150700.7.81.1
kernel-rt - update to 6.4.0-150700.7.81.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.81.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.81.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.81.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.81.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.81.1
dlm-kmp-rt - update to 6.4.0-150700.7.81.1
kernel-rt-debugsource - update to 6.4.0-150700.7.81.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.81.1
gfs2-kmp-rt - update to 6.4.0-150700.7.81.1
kernel-obs-build - update to 6.4.0-150700.53.87.2
kernel-obs-build-debugsource - update to 6.4.0-150700.53.87.2
kernel-azure - update to 6.4.0-150700.53.87.3
kernel-azure-debugsource - update to 6.4.0-150700.53.87.3
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.87.3
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.87.3
kernel-azure-debuginfo - update to 6.4.0-150700.53.87.3
kernel-azure-devel - update to 6.4.0-150700.53.87.3
kernel-default-extra - update to 6.4.0-150700.53.87.3
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.87.3
kernel-default-livepatch-devel - update to 6.4.0-150700.53.87.3
kernel-zfcpdump - update to 6.4.0-150700.53.87.3
kernel-default-livepatch - update to 6.4.0-150700.53.87.3
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.87.3
reiserfs-kmp-default - update to 6.4.0-150700.53.87.3
kernel-docs - update to 6.4.0-150700.53.87.3
kernel-64kb-debugsource - update to 6.4.0-150700.53.87.3
kernel-64kb-debuginfo - update to 6.4.0-150700.53.87.3
kernel-64kb-devel - update to 6.4.0-150700.53.87.3
kernel-64kb - update to 6.4.0-150700.53.87.3
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.87.3
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.87.3
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/68d4d3e78150c7ed7d1195af63ad1e6ace30c661
• https://git.kernel.org/stable/c/85904076cece72ee3194646ad7ac8e6659d999aa
• https://git.kernel.org/stable/c/8b994ac5778a725982fd6a8a3afcaa068d4a93e3
• https://git.kernel.org/stable/c/9c6eace8d07e90f038c89eb3b756d65a7e259d48
• https://git.kernel.org/stable/c/ad3249cdf9d4ba34bb8b1ff3956a4020fdfb5b0a
• https://git.kernel.org/stable/c/cd616aa0449a772a6956abf03358f0ff31720580
• https://git.kernel.org/stable/c/f03425dcbe04aec3c27b9917e97d7d23a2908dda

• Out-of-bounds read in Linux kernel isofs
• Debian update for linux
• openEuler 22.03 LTS SP4 update for kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• Ubuntu update for linux-azure-fde
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more
• Ubuntu update for linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx
• Ubuntu update for linux, linux-aws, linux-aws-5.15 and more