CVE-2026-46104

selinux: use sk blob accessor in socket permission helpers

Published May 28, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

selinux: use sk blob accessor in socket permission helpers

SELinux socket state lives in the composite LSM socket blob.

sock_has_perm() and nlmsg_sock_has_extended_perms() currently
dereference sk->sk_security directly, which assumes the SELinux socket
blob is at offset zero.

In stacked configurations that assumption does not hold. If another LSM
allocates socket blob storage before SELinux, these helpers may read the
wrong blob and feed invalid SID and class values into AVC checks.

Use selinux_sock() instead of accessing sk->sk_security directly.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8566-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8568-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8569-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-8593-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8603-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8618-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8663-1 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-8664-1 Linux kernel (NVIDIA BaseOS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8728-3 Linux kernel (Oracle) vulnerabilities
History
Type Values Removed Values Added
Weaknesses CWE-665
CWE-730
Type Values Removed Values Added
Weaknesses CWE-1083
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
Weaknesses CWE-665
CWE-730
Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: selinux: use sk blob accessor in socket permission helpers SELinux socket state lives in the composite LSM socket blob. sock_has_perm() and nlmsg_sock_has_extended_perms() currently dereference sk->sk_security directly, which assumes the SELinux socket blob is at offset zero. In stacked configurations that assumption does not hold. If another LSM allocates socket blob storage before SELinux, these helpers may read the wrong blob and feed invalid SID and class values into AVC checks. Use selinux_sock() instead of accessing sk->sk_security directly.
Title selinux: use sk blob accessor in socket permission helpers
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Jun 14, 2026, 5:54 PM
Reserved
May 13, 2026, 3:03 PM
Status
Analyzed
Published
May 28, 2026, 10:16 AM
Modified
Jun 25, 2026, 9:18 PM
Severity
Moderate
Public date
May 28, 2026, 12:00 AM