| ID |
CVE-2026-43442
|
| Sažetak |
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. |
| Reference |
|
| CVSS |
| Base: | 7.1 |
| Impact: | 5.2 |
| Exploitability: | 1.8 |
|
| Pristup |
| Vektor | Složenost | Autentikacija |
| LOCAL |
LOW |
LOW |
|
| Impact |
| Povjerljivost | Cjelovitost | Dostupnost |
| HIGH |
NONE |
HIGH |
|
| CVSS vektor |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| Zadnje važnije ažuriranje |
21-05-2026 - 17:10 |
| Objavljeno |
08-05-2026 - 15:16 |
