CVE-2026-43442

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix physical SQE bounds check for SQE_MIXED 128-byte ops When IORING_SETUP_SQE_MIXED is used without IORING_SETUP_NO_SQARRAY, the boundary check for 128-byte SQE operations in io_init_req() validated the logical SQ head position rather than the physical SQE index. The existing check: !(ctx->cached_sq_head & (ctx->sq_entries - 1)) ensures the logical position isn't at the end of the ring, which is correct for NO_SQARRAY rings where physical == logical. However, when sq_array is present, an unprivileged user can remap any logical position to an arbitrary physical index via sq_array. Setting sq_array[N] = sq_entries - 1 places a 128-byte operation at the last physical SQE slot, causing the 128-byte memcpy in io_uring_cmd_sqe_copy() to read 64 bytes past the end of the SQE array. Replace the cached_sq_head alignment check with a direct validation of the physical SQE index, which correctly handles both sq_array and NO_SQARRAY cases.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1f794f9bed3e5cf7250a3b4daf112a72ed1513e9	Patch
https://git.kernel.org/stable/c/6f02c6b196036dbb6defb4647d8707d29b7fe95b	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::

History

No history.

Information

Published : 2026-05-08 15:16

Updated : 2026-06-17 10:49

NVD link : CVE-2026-43442

Mitre link : CVE-2026-43442

CVE.ORG link : CVE-2026-43442

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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