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

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-05-08 14:21
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 ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < 3376b345df155ca36d8611857b41ff7d5183fc38 (git)
Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < 2f3dea284c761c890d676f77d5e55c0c496b4ef4 (git)
Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < 0ad650e60150eda789deca5e78a6a09d26bf8fc9 (git)
Affected: a1d220d9dafa8d76ba60a784a1016c3134e6a1e8 , < e6b899f08066e744f89df16ceb782e06868bd148 (git)
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    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)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.