Improper access control in Linux kernel - CVE-2026-72243

Vulnerability identifier: #VU143349

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-72243

CWE-ID: CWE-284

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to bypass SELinux connect-related permission checks.

The vulnerability exists due to improper access control in the SELinux socket_sendmsg() hook when using TCP Fast Open on TCP or MPTCP stream sockets. A local user can send data with MSG_FASTOPEN to bypass SELinux connect-related permission checks.

Linux kernel
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
kernel-debug-devel (Red Hat package)
kernel-debug-devel-matched (Red Hat package)
kernel-devel (Red Hat package)
kernel-devel-matched (Red Hat package)
kernel-headers (Red Hat package)
perf (Red Hat package)
python3-perf (Red Hat package)
kernel-zfcpdump-devel (Red Hat package)
kernel-zfcpdump-devel-matched (Red Hat package)
kernel-64k-debug-devel (Red Hat package)
kernel-64k-debug-devel-matched (Red Hat package)
kernel-64k-devel (Red Hat package)
kernel-64k-devel-matched (Red Hat package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-debug-devel (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-debug-devel-matched (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-devel (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-devel-matched (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-headers (Red Hat package) - update to 6.12.0-211.59.1.el10_2
perf (Red Hat package) - update to 6.12.0-211.59.1.el10_2
python3-perf (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-zfcpdump-devel (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-zfcpdump-devel-matched (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-64k-debug-devel (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-64k-debug-devel-matched (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-64k-devel (Red Hat package) - update to 6.12.0-211.59.1.el10_2
kernel-64k-devel-matched (Red Hat package) - update to 6.12.0-211.59.1.el10_2

• https://git.kernel.org/stable/c/11406d0d7e11b4e525bb2ace2c70107031d058da
• https://git.kernel.org/stable/c/44c74d27d1b9aaa99fa8a83640c1223575262b80
• https://git.kernel.org/stable/c/646ebbc5f2ff9147d084e1213143f091026a611c
• https://git.kernel.org/stable/c/d028bc080a0dcd6a7f8e1ae1bd32dda696505ba3
• https://git.kernel.org/stable/c/e507633bf76bccf1a6af27771fb0d6e2862b7eac
• https://git.kernel.org/stable/c/fc633a598206d4f23af782db7c0b5f3a82751d2c

• Improper access control in Linux kernel selinux
• Red Hat Enterprise Linux 10 update for kernel