Junglewise Threat Intelligence

CVE-2025-38656: Linux Kernel iwlwifi use after free in iwl_op_mode_dvm_start

CVE-2025-38656 · Severity: high · CVSS 7.8 · Published 2025-08-22

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability in the Linux kernel's Intel Wi-Fi driver (iwlwifi) could allow a local user to cause a system crash or potentially execute unauthorized actions. The issue stems from improper error handling during the initialization of the Wi-Fi hardware, which can lead to memory corruption. This affects systems using specific Intel wireless adapters and could impact system stability and data integrity.

Technical details

A use-after-free (UAF) vulnerability exists in the Linux kernel's iwlwifi driver within the 'iwl_op_mode_dvm_start()' function in 'drivers/net/wireless/intel/iwlwifi/dvm/main.c'. The root cause is a failure to preserve and return the correct error code when 'iwl_setup_deferred_work()' fails; the function incorrectly returns NULL (ERR_PTR(0)) instead of a proper error pointer. This improper return value can lead to a use-after-free condition involving debugfs components during cleanup or subsequent operations. An attacker with local access could exploit this to cause a denial of service (system crash) or potentially achieve privilege escalation. Patches have been released for various stable kernel branches including 5.4.y, 5.10.y, 5.15.y, 6.1.y, 6.6.y, and 6.12.y.

Affected products

  • Linux Linux Kernel 5.4.297 to 5.5, 5.10.241 to 5.11, 5.15.190 to 5.16, 6.1.148 to 6.2, 6.6.102 to 6.7, 6.12.42 to 6.13

Timeline

  • 2025-08-22: disclosed
  • 2025-08-22: advisory
  • 2025-08-15: patched: Patched in stable branches

References

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