CVE-2026-43391 (GCVE-0-2026-43391)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-09-07 15:44
VLAI
Title
nsfs: tighten permission checks for handle opening
Summary
In the Linux kernel, the following vulnerability has been resolved: nsfs: tighten permission checks for handle opening 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 7018 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5222470b2fbb3740f931f189db33dd1367b1ae75 , < 24ebaf6676ae4f74f4856eb645959b15e62bc1b4 (git)
Affected: 5222470b2fbb3740f931f189db33dd1367b1ae75 , < 1797ee11451f1b2be69863a9f5bd43b948813fdf (git)
Affected: 5222470b2fbb3740f931f189db33dd1367b1ae75 , < d2324a9317f00013facb0ba00b00440e19d2af5e (git)
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Linux Linux Affected: 6.18
Unaffected: 0 , < 6.18 (semver)
Unaffected: 6.18.50 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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