CVE-2025-21904: Linux kernel · caif_virtio: fix wrong pointer check in cfv_probe()
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 29 Oct 2026, 22:52 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 Apr 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
Description
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().
References
- nvd.nist.gov/vuln/detail/CVE-2025-21904 (opens in a new tab)
- git.kernel.org/stable/c/29e0cd296c87240278e2f7ea4cf3f496b60c03af (opens in a new tab)
- git.kernel.org/stable/c/56cddf71cce3b15b078e937fadab29962b6f6643 (opens in a new tab)
- git.kernel.org/stable/c/597c27e5f04cb50e56cc9aeda75d3e42b6b89c3e (opens in a new tab)
- git.kernel.org/stable/c/7b5fe58959822e6cfa884327cabba6be3b01883d (opens in a new tab)
- git.kernel.org/stable/c/8e4e08ca4cc634b337bb74bc9a70758fdeda0bcb (opens in a new tab)
- git.kernel.org/stable/c/90d302619ee7ce5ed0c69c29c290bdccfde66418 (opens in a new tab)
- git.kernel.org/stable/c/990fff6980d0c1693d60a812f58dbf93eab0473f (opens in a new tab)
- git.kernel.org/stable/c/a466fd7e9fafd975949e5945e2f70c33a94b1a70 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/05/msg00030.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/05/msg00045.html (opens in a new tab)