CVE-2025-39976
futex: Use correct exit on failure from futex_hash_allocate_default()
Description
In the Linux kernel, the following vulnerability has been resolved: futex: Use correct exit on failure from futex_hash_allocate_default() copy_process() uses the wrong error exit path from futex_hash_allocate_default(). After exiting from futex_hash_allocate_default(), neither tasklist_lock nor siglock has been acquired. The exit label bad_fork_core_free unlocks both of these locks which is wrong. The next exit label, bad_fork_cancel_cgroup, is the correct exit. sched_cgroup_fork() did not allocate any resources that need to freed. Use bad_fork_cancel_cgroup on error exit from futex_hash_allocate_default().
INFO
Published Date :
Oct. 15, 2025, 8:15 a.m.
Last Modified :
Oct. 16, 2025, 3:29 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Apply kernel patch for futex error handling.
- Ensure correct lock management during fork.
- Update system to the patched kernel version.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-39976.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/4ec3c15462b9f44562f45723a92e2807746ba7d1 | |
| https://git.kernel.org/stable/c/f1635765cd0fdbf27b04d9a50be91a01b5adda13 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-39976 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-39976
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-39976 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-39976 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Oct. 15, 2025
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: futex: Use correct exit on failure from futex_hash_allocate_default() copy_process() uses the wrong error exit path from futex_hash_allocate_default(). After exiting from futex_hash_allocate_default(), neither tasklist_lock nor siglock has been acquired. The exit label bad_fork_core_free unlocks both of these locks which is wrong. The next exit label, bad_fork_cancel_cgroup, is the correct exit. sched_cgroup_fork() did not allocate any resources that need to freed. Use bad_fork_cancel_cgroup on error exit from futex_hash_allocate_default(). Added Reference https://git.kernel.org/stable/c/4ec3c15462b9f44562f45723a92e2807746ba7d1 Added Reference https://git.kernel.org/stable/c/f1635765cd0fdbf27b04d9a50be91a01b5adda13