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CVE-2026-81009 Details

Description

In the Linux kernel, the following vulnerability has been resolved: io_uring/query: cap user size passed to copy_struct_to_user io_handle_query_entry() clamps hdr.size for the inbound copy_from_user() but keeps the original user value as usize. copy_struct_to_user() uses that usize and, when it is larger than the kernel result, clear_user()s the trailing bytes. As hdr.size is a __u32, a query can request nearly 4 GiB of zeroing, including on the error path where res_size stays 0. The interface is reachable without a ring via IORING_REGISTER_QUERY. Reject sizes larger than PAGE_SIZE, as recommended for copy_struct_* interfaces.

Metrics

CVSS 3.x Severity and Vector Strings:

No CVSS 3.x data is available for this CVE.

References to Advisories, Solutions, and Tools

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URL	Source(s)	Tag(s)
https://git.kernel.org/stable/c/2b8ad4981ecedb14c1fdd811ab977010b23933e6	kernel.org
https://git.kernel.org/stable/c/417e02f7b6051765b91cf1289071882eebd172e0	kernel.org
https://git.kernel.org/stable/c/ba77efee1b95b4ad7559b1cdbe7cd7fa36dca95b	kernel.org

Weakness Enumeration

No weakness enumeration is available for this CVE.

Affected Products

No affected product data is available for this CVE.

Change History

1 change record found show changes