High severity · published May 8, 2026
CVE-2026-43403
nsfs: tighten permission checks for ns iteration ioctls
8.8
CVSS
0.1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
6.12 before 6.12.78; 6.13 before 6.18.20; 6.19 before 6.19.9; 7.0; 7.0 · source: NVD
LI
Linux · Linux
a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 before 3376b345df155ca36d8611857b41ff7d5183fc38; a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 before 2f3dea284c761c890d676f77d5e55c0c496b4ef4; a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 before 0ad650e60150eda789deca5e78a6a09d26bf8fc9; a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 before e6b899f08066e744f89df16ceb782e06868bd148; 6.12 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-43403
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-43403
Patch
https://git.kernel.org/stable/c/0ad650e60150eda789deca5e78a6a09d26bf8fc9
Patch
https://git.kernel.org/stable/c/2f3dea284c761c890d676f77d5e55c0c496b4ef4
Patch
https://git.kernel.org/stable/c/3376b345df155ca36d8611857b41ff7d5183fc38
Patch
https://git.kernel.org/stable/c/e6b899f08066e744f89df16ceb782e06868bd148
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