CVE WatchJul 30, 2026

CVE-2025-39698

In the Linux kernel, the following vulnerability has been resolved: io_uring/futex: ensure io_futex_wait() cleans up properly on failure T

CVSS

7.8

High

EPSS

0.2%

KEV

—

Exploit Today

0-100

Published: Sep 5, 2025 · Last modified: Jul 30, 2026 · CWE-416 · CWE-672

EPSS · 30d

0.2%EPSS · 30 days0.2%

2026-07-122026-08-08

Technical description

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.

Official references

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