CVE-2026-43403 (GCVE-0-2026-43403)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-08-05 12:27
VLAI
Title
nsfs: tighten permission checks for ns iteration ioctls
Summary
In the Linux kernel, the following vulnerability has been resolved: nsfs: tighten permission checks for ns iteration ioctls Even privileged services should not necessarily be able to see other privileged service's namespaces so they can't leak information to each other. Use may_see_all_namespaces() helper that centralizes this policy until the nstree adapts.
Severity
8.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6637 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < 3376b345df155ca36d8611857b41ff7d5183fc38 (git)
Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < 2f3dea284c761c890d676f77d5e55c0c496b4ef4 (git)
Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < 0ad650e60150eda789deca5e78a6a09d26bf8fc9 (git)
Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < e6b899f08066e744f89df16ceb782e06868bd148 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.78 , ≤ 6.12.* (semver)
Unaffected: 6.18.20 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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}



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