cbcvebase.
CVE-2025-39793
published 2025-09-12

CVE-2025-39793: In the Linux kernel, the following vulnerability has been resolved: io_uring/memmap: cast nr_pages to size_t before shifting If the allocated size exceeds…

PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.14%
3.9th percentile
In the Linux kernel, the following vulnerability has been resolved: io_uring/memmap: cast nr_pages to size_t before shifting If the allocated size exceeds UINT_MAX, then it's necessary to cast the mr->nr_pages value to size_t to prevent it from overflowing. In practice this isn't much of a concern as the required memory size will have been validated upfront, and accounted to the user. And > 4GB sizes will be necessary to make the lack of a cast a problem, which greatly exceeds normal user locked_vm settings that are generally in the kb to mb range. However, if root is used, then accounting isn't done, and then it's possible to hit this issue.

Affected

8 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.16.3-1 (forky)linux 6.16.3-1 (forky)
linuxlinux
linuxlinux>= 087f997870a948820ec366701d178f402c6a23a3 < c6a2706e08b8a1b2d3740161c0977d38e596c1eec6a2706e08b8a1b2d3740161c0977d38e596c1ee
linuxlinux>= 087f997870a948820ec366701d178f402c6a23a3 < a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3aa69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a
linuxlinux>= 087f997870a948820ec366701d178f402c6a23a3 < 33503c083fda048c77903460ac0429e1e2c0e34133503c083fda048c77903460ac0429e1e2c0e341
linuxlinux_kernel>= 0 < 6.16.3-16.16.3-1
linuxlinux_kernel>= 6.14 < 6.15.116.15.11
linuxlinux_kernel>= 6.16 < 6.16.26.16.2

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8LOW
vendor_redhat7.8HIGH
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