CVE-2025-39698 (GCVE-0-2025-39698)
Vulnerability from cvelistv5
Published
2025-09-05 17:21
Modified
2026-08-05 12:04
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/futex: ensure io_futex_wait() cleans up properly on failure The io_futex_data is allocated upfront and assigned to the io_kiocb async_data field, but the request isn't marked with REQ_F_ASYNC_DATA at that point. Those two should always go together, as the flag tells io_uring whether the field is valid or not. Additionally, on failure cleanup, the futex handler frees the data but does not clear ->async_data. Clear the data and the flag in the error path as well. Thanks to Trend Micro Zero Day Initiative and particularly ReDress for reporting this.
References
Impacted products
Vendor Product Version
Linux Linux Version: 194bb58c6090e39bd7d9b9c888a079213628e1f6
Version: 194bb58c6090e39bd7d9b9c888a079213628e1f6
Version: 194bb58c6090e39bd7d9b9c888a079213628e1f6
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