cbcvebase.
CVE-2021-3491
published 2021-06-04

CVE-2021-3491: The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being…

PriorityP347high8.8CVSS 3.1
AVLACLPRLUINSCCHIHAH
EPSS
0.63%
46.1th percentile
The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc//mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1).

Affected

16 ranges
VendorProductVersion rangeFixed in
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
debianlinux< linux 5.10.38-1 (bookworm)linux 5.10.38-1 (bookworm)
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 5.11 < 5.11.215.11.21
linuxlinux_kernel>= 5.12 < 5.12.45.12.4
linuxlinux_kernel>= 5.7 < 5.10.375.10.37
linuxlinux_kernel>= linux-5.10.y < v5.10.37v5.10.37
linuxlinux_kernel>= linux-5.11.y < v5.11.21v5.11.21
linuxlinux_kernel>= linux-5.12.y < v5.12.4v5.12.4
linuxlinux_kernel>= trunk < v5.13-rc4v5.13-rc4
linuxlinux_kernel>= v5.7-rc1 < 5.7*5.7*

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
nvdv2.07.2HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
osv8.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu7.8HIGH
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