CVE-ID

CVE-2021-3491

• CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
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/<PID>/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).
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
Assigning CNA
Canonical Ltd.
Date Record Created
20210409 Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20210409)
Votes (Legacy)
Comments (Legacy)
Proposed (Legacy)
N/A
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