PT-2026-39064 · Linux · Linux Kernel

Published 2026-05-08 · Updated 2026-05-15 · CVE-2026-43403

Positive Technologies (AI Summary)

CVSS v3.1

8.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description Insufficient permission checks in the nsfs (namespace filesystem) for namespace iteration ioctls could allow privileged services to view namespaces belonging to other privileged services, potentially leading to information leakage. The issue is addressed by implementing the may see all namespaces() helper to centralize the permission policy.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-43403

Affected Products

Linux Kernel

References · 15

• https://osv.dev/vulnerability/UBUNTU-CVE-2026-43403 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-43403 · Vendor Advisory
• https://git.kernel.org/stable/c/e6b899f08066e744f89df16ceb782e06868bd148 · Patch
• https://git.kernel.org/stable/c/3376b345df155ca36d8611857b41ff7d5183fc38 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-43403 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-43403 · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-43403 · Vendor Advisory
• https://git.kernel.org/stable/c/0ad650e60150eda789deca5e78a6a09d26bf8fc9 · Patch
• https://cve.org/CVERecord?id=CVE-2026-43403 · Security Note
• https://git.kernel.org/stable/c/2f3dea284c761c890d676f77d5e55c0c496b4ef4 · Patch
• https://ubuntu.com/security/CVE-2026-43403 · Vendor Advisory
• https://docs.bell-sw.com/security/cves/CVE-2026-43403 · Note
• https://twitter.com/hetmehtaa/status/2055151398283837677 · Twitter Post
• https://git.kernel.org/linus/e6b899f08066e744f89df16ceb782e06868bd148 · Note
• https://twitter.com/CVEnew/status/2052767677387768132 · Twitter Post