CVE-2026-46104: linux kernel vulnerability

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.
CVE-2026-46104CVSS 5.5Linux

CVE-2026-46104: linux kernel vulnerability

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.

CVSS
5.5 MEDIUM
EPSS
2.23%
Known exploited
not in KEV
Product
linux kernel

What is known

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.

Sources

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