Vulnerabilities

Vulnerability · 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 The io_futex_data is allocated upfront and

Published Sep 5, 2025 · catalog updated Oct 19, 2026 · Linux Linux

Check this week

CVE-2025-39698 is not in CISA KEV. FIRST estimates a 19.00% chance of exploitation in the next 30 days. Check whether you run Linux Linux.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High8.8
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
19.00%
Remediation
Advisory link
Affected products
cpe linux/linux kernel · vendor Linux Linux patch: 6.16.4

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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe linux/linux kernel6.17
  • vendor Linux Linux patch: 6.16.4patch: 6.16.4

How to fix CVE-2025-39698

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

CVE-2025-39698 is not in CISA KEV. FIRST estimates a 19.00% chance of exploitation in the next 30 days. Check whether you run Linux Linux.

Which versions are affected?

Compare what you have installed with linux/linux kernel 6.17; Linux Linux patch: 6.16.4 patch: 6.16.4. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-416: Use After Free; CWE-672. EPSS 19.00%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Sep 5, 2025 · NIST NVD

    Detected

    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

  2. Oct 19, 2026 · NIST NVD

    Updated

    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

Sources

  • EUVDVulnerability recordEUVD-2025-31205

    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 tha

    euvd.enisa.europa.eu
  • NIST NVDVulnerability recordCVE-2025-39698

    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 t

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 19, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.