CVE-2025-68773 json
spi: fsl-cpm: Check length parity before switching to 16 bit mode
published 2026-01-13 9 mo ago modified 2026-10-15 25 d ago also EUVD-2026-2313
- 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 14%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
spi: fsl-cpm: Check length parity before switching to 16 bit mode
Commit fc96ec826bce ("spi: fsl-cpm: Use 16 bit mode for large transfers with even size") failed to make sure that the size is really even before switching to 16 bit mode. Until recently the problem went unnoticed because kernfs uses a pre-allocated bounce buffer of size PAGE_SIZE for reading EEPROM.
But commit 8ad6249c51d0 ("eeprom: at25: convert to spi-mem API") introduced an additional dynamically allocated bounce buffer whose size is exactly the size of the transfer, leading to a buffer overrun in the fsl-cpm driver when that size is odd.
Add the missing length parity verification and remain in 8 bit mode when the length is not even.
Patch / fix
- Linux Linux 4.15, 4.20, 5.5, 5.10.248, 5.15.198, 6.1.160, 6.3, 6.4, 6.6.120, 6.12.64, 6.18.3, 6.19
- linux Debian 12 6.1.162-1
- linux Debian 13 6.12.69-1
- linux Debian 14 6.18.3-1
debian advisories DEBIAN-CVE-2025-68773
- linux Ubuntu 24.04 LTS 6.8.0-110.110
- linux Ubuntu 25.10 6.17.0-22.22
- linux-aws Ubuntu 24.04 LTS 6.8.0-1052.55
- linux-aws Ubuntu 25.10 6.17.0-1012.12
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1054.57
- linux-gcp Ubuntu 25.10 6.17.0-1012.12
- linux-gke Ubuntu 24.04 LTS 6.8.0-1050.56
- linux-ibm Ubuntu 24.04 LTS 6.8.0-1051.51
ubuntu advisories UBUNTU-CVE-2025-68773
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-rt Linux Micro 6.2 6.12.0-160000.26.1
- kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.26.1
- kernel-source SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.26.1
- kernel-default SLES 16.0, SLE High Availability Extension 16.0, Linux Micro 6.2 +1 more 6.12.0-160000.26.1
- kernel-default-base SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.26.1.160000.2.7
- kernel-syms SLES 16.0, Linux Micro Extras 6.2, SLES for SAP applications 16.0 6.12.0-160000.26.1
suse advisories SUSE-SU-2026:20845-1SUSE-SU-2026:20876-1SUSE-SU-2026:20555-1SUSE-SU-2026:20599-1SUSE-SU-2026:20615-1SUSE-SU-2026:20570-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.26.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.26.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.26.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.26.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.26.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.26.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.26.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.26.1
opensuse advisories openSUSE-SU-2026:20287-1
- git.kernel.org/stable/c/c8f1d35076b78df61ace737e41cc1f4b7b63236c commit
- git.kernel.org/stable/c/9c34a4a2ead00979d203a8c16bea87f0ef5291d8 commit
- git.kernel.org/stable/c/837a23a11e0f734f096c7c7b0778d0e625e3dc87 commit
- git.kernel.org/stable/c/3dd6d01384823e1bd8602873153d6fc4337ac4fe commit
- git.kernel.org/stable/c/743cebcbd1b2609ec5057ab474979cef73d1b681 commit
- git.kernel.org/stable/c/be0b613198e6bfa104ad520397cab82ad3ec1771 commit
- git.kernel.org/stable/c/1417927df8049a0194933861e9b098669a95c762 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-2025-68773 updated
kernel: spi: fsl-cpm: Check length parity before switching to 16 bit mode
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more 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 more Red Hat Enterprise Linux 10 kernelnot 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
cisa ICSA-26-295-11 updated cvss 5.5
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP
-
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.7 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.7affected: mitigation, no fix available
Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf
cisa ICSA-26-209-04 updated cvss 5.5
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP
-
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.6 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.6affected: mitigation, no fix available
Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
- Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
- Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
- Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
Classification
- Technology feeds
References
- git.kernel.org /stable/c/c8f1d35076b78df61ace737e41cc1f4b7b63236c
- git.kernel.org /stable/c/9c34a4a2ead00979d203a8c16bea87f0ef5291d8
- git.kernel.org /stable/c/837a23a11e0f734f096c7c7b0778d0e625e3dc87
- git.kernel.org /stable/c/3dd6d01384823e1bd8602873153d6fc4337ac4fe
- git.kernel.org /stable/c/743cebcbd1b2609ec5057ab474979cef73d1b681
- git.kernel.org /stable/c/be0b613198e6bfa104ad520397cab82ad3ec1771
- git.kernel.org /stable/c/1417927df8049a0194933861e9b098669a95c762
- cert-portal.siemens.com /productcert/html/ssa-019113.html
- cert-portal.siemens.com /productcert/html/ssa-457936.html
Sources
- CVE List CVE-2025-68773
- NVD CVE-2025-68773
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