NULL pointer dereference in Linux

CVE-2025-21870

In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers Other, non DAI copier widgets could have the same stream name (sname) as the ALH copier and in that case the copier->data is NULL, no alh_data is attached, which could lead to NULL pointer dereference. We could check for this NULL pointer in sof_ipc4_prepare_copier_module() and avoid the crash, but a similar loop in sof_ipc4_widget_setup_comp_dai() will miscalculate the ALH device count, causing broken audio. The correct fix is to harden the matching logic by making sure that the 1. widget is a DAI widget - so dai = w->private is valid 2. the dai (and thus the copier) is ALH copier

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 (8.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 8.9% 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-2025-21870: 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 a150345aa758492e05d2934f318ce7c2566b1cfe, 6.0, 0
  • Linux Kernel — versions 6.14

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-21870?
CVE-2025-21870 is a high-severity vulnerability in Linux, classified under NULL Pointer Dereference. CVSS score: 7.8/10. Published 2025-03-27.
How severe is CVE-2025-21870?
High severity. CVSS v3 base score is 7.8 out of 10.