Use After Free in Linux

CVE-2025-38056

In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: Intel: hda: Fix UAF when reloading module hda_generic_machine_select() appends -idisp to the tplg filename by allocating a new string with devm_kasprintf(), then stores the string right back into the global variable snd_soc_acpi_intel_hda_machines. When the module is unloaded, this memory is freed, resulting in a global variable pointing to freed memory. Reloading the module then triggers a use-after-free: BUG: KFENCE: use-after-free read in string+0x48/0xe0 Use-after-free read at 0x00000000967e0109 (in kfence-#99): string+0x48/0xe0 vsnprintf+0x329/0x6e0 devm_kvasprintf+0x54/0xb0 devm_kasprintf+0x58/0x80 hda_machine_select.cold+0x198/0x17a2 [snd_sof_intel_hda_generic] sof_probe_work+0x7f/0x600 [snd_sof] process_one_work+0x17b/0x330 worker_thread+0x2ce/0x3f0 kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 kfence-#99: 0x00000000198a940f-0x00000000ace47d9d, size=64, cache=kmalloc-64 allocated by task 333 on cpu 8 at 17.798069s (130.453553s ago): devm_kmalloc+0x52/0x120 devm_kvasprintf+0x66/0xb0 devm_kasprintf+0x58/0x80 hda_machine_select.cold+0x198/0x17a2 [snd_sof_intel_hda_generic] sof_probe_work+0x7f/0x600 [snd_sof] process_one_work+0x17b/0x330 worker_thread+0x2ce/0x3f0 kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 freed by task 1543 on cpu 4 at 141.586686s (6.665010s ago): release_nodes+0x43/0xb0 devres_release_all+0x90/0xf0 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1c1/0x200 driver_detach+0x48/0x90 bus_remove_driver+0x6d/0xf0 pci_unregister_driver+0x42/0xb0 __do_sys_delete_module+0x1d1/0x310 do_syscall_64+0x82/0x190 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fix it by copying the match array with devm_kmemdup_array() before we modify it.

Vulnerability class: Use-After-Free

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (7.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 7.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-38056: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

  • Linux — versions 5458411d75947a4212e50a401ec0a98d4c6c931b, 6.12, 0
  • Linux Kernel — versions 6.15

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-38056?
CVE-2025-38056 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2025-06-18.
How severe is CVE-2025-38056?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2025-38056 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.