CVE-2025-21666 (GCVE-0-2025-21666)

Vulnerability from cvelistv5 – Published: 2025-01-31 11:25 – Updated: 2026-10-15 01:02
VLAI
Title
vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]
Summary
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.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-01 19:52 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6641 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < daeac89cdb03d30028186f5ff7dc26ec8fa843e7 (git)
Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 9e5fed46ccd2c34c5fa5a9c8825ce4823fdc853e (git)
Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < b52e50dd4fabd12944172bd486a4f4853b7f74dd (git)
Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < bc9c49341f9728c31fe248c5fbba32d2e81a092b (git)
Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < c23d1d4f8efefb72258e9cedce29de10d057f8ca (git)
Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 91751e248256efc111e52e15115840c35d85abaf (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.5
Unaffected: 0 , < 5.5 (semver)
Unaffected: 5.10.234 , ≤ 5.10.* (semver)
Unaffected: 5.15.177 , ≤ 5.15.* (semver)
Unaffected: 6.1.127 , ≤ 6.1.* (semver)
Unaffected: 6.6.74 , ≤ 6.6.* (semver)
Unaffected: 6.12.11 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Affected: 0 , < * (custom)
guessed Create a notification for this product.
Show details on NVD website
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}



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Sightings

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Nomenclature

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