CVE-2025-68237 json
mtdchar: fix integer overflow in read/write ioctls
published 2025-12-16 10 mo ago modified 2026-10-14 25 d ago also EUVD-2025-203659
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 8%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
mtdchar: fix integer overflow in read/write ioctls
The "req.start" and "req.len" variables are u64 values that come from the user at the start of the function. We mask away the high 32 bits of "req.len" so that's capped at U32_MAX but the "req.start" variable can go up to U64_MAX which means that the addition can still integer overflow.
Use check_add_overflow() to fix this bug.
Patch / fix
- Linux Linux 6.1.159, 6.6.118, 6.12.60, 6.17.10, 6.18
- linux Debian 12 6.1.159-1
- linux Debian 13 6.12.63-1
- linux Debian 14 6.17.10-1
debian advisories DEBIAN-CVE-2025-68237
- linux Ubuntu 24.04 LTS 6.8.0-106.106
- linux Ubuntu 25.10 6.17.0-19.19
- linux-aws Ubuntu 24.04 LTS 6.8.0-1050.53
- linux-aws Ubuntu 25.10 6.17.0-1009.9
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1052.55
- linux-gcp Ubuntu 25.10 6.17.0-1009.9
- linux-gke Ubuntu 24.04 LTS 6.8.0-1048.53
- linux-ibm Ubuntu 24.04 LTS 6.8.0-1049.49
ubuntu advisories UBUNTU-CVE-2025-68237
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
- kernel-source-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
- kernel-source Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
- kernel-default Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
- kernel-kvmsmall Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
- kernel-default-base Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1.21.16
- kernel-rt Linux Micro 6.2 6.12.0-160000.9.1
- kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.9.1
suse advisories SUSE-SU-2026:20845-1SUSE-SU-2026:20876-1SUSE-SU-2026:20477-1SUSE-SU-2026:20498-1SUSE-SU-2026:20207-1SUSE-SU-2026:20220-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.9.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.9.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.9.1
opensuse advisories openSUSE-SU-2026:20145-1
- git.kernel.org/stable/c/f37efdd97fd1ec3e0d0f1eec279c8279e28f981e commit
- git.kernel.org/stable/c/457376c6fbf0c69326a9bf1f72416225f681192b commit
- git.kernel.org/stable/c/eb9361484814fb12f3b7544b33835ea67d7a6a97 commit
- git.kernel.org/stable/c/37944f4f8199cd153fef74e95ca268020162f212 commit
- git.kernel.org/stable/c/e4185bed738da755b191aa3f2e16e8b48450e1b8 commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2025-68237 updated cvss 6.7
kernel: mtdchar: fix integer overflow in read/write ioctls
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 10 kernelaffected: no fix available “Fix deferred”
-
Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 morenot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/f37efdd97fd1ec3e0d0f1eec279c8279e28f981e
- git.kernel.org /stable/c/457376c6fbf0c69326a9bf1f72416225f681192b
- git.kernel.org /stable/c/eb9361484814fb12f3b7544b33835ea67d7a6a97
- git.kernel.org /stable/c/37944f4f8199cd153fef74e95ca268020162f212
- git.kernel.org /stable/c/e4185bed738da755b191aa3f2e16e8b48450e1b8
Sources
- CVE List CVE-2025-68237
- NVD CVE-2025-68237
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