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Fencer Intel
medium 5.5

CVE-2025-39921 json

spi: microchip-core-qspi: stop checking viability of op->max_freq in supports_op callback

published last yr. modified 19d ago also EUVD-2025-32884

cvss
5.5
version 3.1, CNA
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:

spi: microchip-core-qspi: stop checking viability of op->max_freq in supports_op callback

In commit 13529647743d9 ("spi: microchip-core-qspi: Support per spi-mem operation frequency switches") the logic for checking the viability of op->max_freq in mchp_coreqspi_setup_clock() was copied into mchp_coreqspi_supports_op(). Unfortunately, op->max_freq is not valid when this function is called during probe but is instead zero. Accordingly, baud_rate_val is calculated to be INT_MAX due to division by zero, causing probe of the attached memory device to fail.

Seemingly spi-microchip-core-qspi was the only driver that had such a modification made to its supports_op callback when the per_op_freq capability was added, so just remove it to restore prior functionality.

Patch / fix

  • Linux Linux 6.16.6, 6.17
  • linux Debian 14 6.16.6-1

debian advisories DEBIAN-CVE-2025-39921

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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-2025-39921 updated

kernel: spi: microchip-core-qspi: stop checking viability of op->max_freq in supports_op callback

  • 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 kernel
    not 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 SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
9mo ago

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.