Medium 5.5Published Jan 31, 2025

CVE-2025-21666vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]

Updated under an hour ago (Oct 28, 2026, 12:30 PM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: vsock: prevent null-ptr-deref in vsock_*[has_data|has_space] Recent reports have shown how we sometimes call vsock_*_has_data() when a vsock socket has been de-assigned from a transport (see attached links), but we shouldn't. Previous commits should have solved the real problems, but we may have more in the future, so to avoid null-ptr-deref, we can return 0 (no space, no data available) but with a warning. This way the code should continue to run in a nearly consistent state and have a warning that allows us to debug future problems.

CVSS: 5.5 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-476
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Not yet received
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from c0cfa2d8a788fcf45df5bf4070ab2474c88d543a before daeac89cdb03d30028186f5ff7dc26ec8fa843e7; from c0cfa2d8a788fcf45df5bf4070ab2474c88d543a before 9e5fed46ccd2c34c5fa5a9c8825ce4823fdc853e; from c0cfa2d8a788fcf45df5bf4070ab2474c88d543a before b52e50dd4fabd12944172bd486a4f4853b7f74dd; from c0cfa2d8a788fcf45df5bf4070ab2474c88d543a before bc9c49341f9728c31fe248c5fbba32d2e81a092b; from c0cfa2d8a788fcf45df5bf4070ab2474c88d543a before c23d1d4f8efefb72258e9cedce29de10d057f8ca; from c0cfa2d8a788fcf45df5bf4070ab2474c88d543a before 91751e248256efc111e52e15115840c35d85abaf	CNA record
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name)	all versions	CISA ADP

References

References

https://git.kernel.org/stable/c/daeac89cdb03d30028186f5ff7dc26ec8fa843e7
https://git.kernel.org/stable/c/9e5fed46ccd2c34c5fa5a9c8825ce4823fdc853e
https://git.kernel.org/stable/c/b52e50dd4fabd12944172bd486a4f4853b7f74dd
https://git.kernel.org/stable/c/bc9c49341f9728c31fe248c5fbba32d2e81a092b
https://git.kernel.org/stable/c/c23d1d4f8efefb72258e9cedce29de10d057f8ca
https://git.kernel.org/stable/c/91751e248256efc111e52e15115840c35d85abaf

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.