CVE-2025-39793
HIGH EPSS 3.8%
Published Sep 12, 20259mo ago · Modified Jun 17, 20261w ago
7.8 CVSS 3.1
Published Sep 12, 2025 9mo ago
Last Modified Jun 17, 2026 1w ago
Description
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High
Threat Intelligence
EPSS Exploit Probability
3.8% percentile
Exploit & Patch Status
No Known Exploit
Patch Available
Affected Products 2
References 3
- git.kernel.org https://git.kernel.org/stable/c/33503c083fda048c77903460ac0429e1e2c0e341
- git.kernel.org https://git.kernel.org/stable/c/a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a
- git.kernel.org https://git.kernel.org/stable/c/c6a2706e08b8a1b2d3740161c0977d38e596c1ee
Remediation
- git.kernel.org https://git.kernel.org/stable/c/33503c083fda048c77903460ac0429e1e2c0e341
- git.kernel.org https://git.kernel.org/stable/c/a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a
- git.kernel.org https://git.kernel.org/stable/c/c6a2706e08b8a1b2d3740161c0977d38e596c1ee