NULL pointer dereference in Linux

CVE-2025-21904

In the Linux kernel, the following vulnerability has been resolved: caif_virtio: fix wrong pointer check in cfv_probe() del_vqs() frees virtqueues, therefore cfv->vq_tx pointer should be checked for NULL before calling it, not cfv->vdev. Also the current implementation is redundant because the pointer cfv->vdev is dereferenced before it is checked for NULL. Fix this by checking cfv->vq_tx for NULL instead of cfv->vdev before calling del_vqs().

EPSS: 0.002 (10.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-21904?
CVE-2025-21904 is a medium-severity vulnerability in Linux, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2025-04-01.
How severe is CVE-2025-21904?
Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2025-21904 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.