Vulnerability Database

374,345

Total vulnerabilities in the database

CVE-2025-39921 — linux / linux_kernel

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.

  • Published: Oct 1, 2025
  • Updated: Dec 15, 2025
  • CVE: CVE-2025-39921
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.5
  • AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

No CWE or OWASP classifications available.

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