Linux hwe edge: In the Linux kernel, the following vulnerability has been resolved: futex: Use correct exit on failure from futex_hash_allocate_default()… (CVE-2025-39976)
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().
AI Analysis
Technical Summary
The Linux kernel contained a vulnerability (CVE-2025-39976) in the futex subsystem where copy_process() used an incorrect error exit path after a failure in futex_hash_allocate_default(). Specifically, the exit label bad_fork_core_free was used incorrectly, unlocking tasklist_lock and siglock which had not been acquired, leading to potential kernel instability or security risks. The correct exit label, bad_fork_cancel_cgroup, does not unlock these locks and is now used to properly handle the error. This issue has been resolved in the Linux kernel.
Potential Impact
The vulnerability could cause improper lock handling in the kernel, potentially resulting in system instability, crashes, or security issues due to unlocking locks that were never acquired. The CVSS vector indicates high impact on confidentiality, integrity, and availability (C:H/I:H/A:H), but no known exploits are reported in the wild.
Mitigation Recommendations
A fix for this vulnerability has been implemented in the Linux kernel by correcting the error exit path in copy_process() to use the proper label. Users should apply the official kernel updates or patches that include this fix. Since no vendor advisory or patch links are provided here, check the official Linux kernel repositories or vendor advisories for the specific patch and update instructions.
Linux hwe edge: In the Linux kernel, the following vulnerability has been resolved: futex: Use correct exit on failure from futex_hash_allocate_default()… (CVE-2025-39976)
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().
CVSS v3.1
Score 7.8high
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel contained a vulnerability (CVE-2025-39976) in the futex subsystem where copy_process() used an incorrect error exit path after a failure in futex_hash_allocate_default(). Specifically, the exit label bad_fork_core_free was used incorrectly, unlocking tasklist_lock and siglock which had not been acquired, leading to potential kernel instability or security risks. The correct exit label, bad_fork_cancel_cgroup, does not unlock these locks and is now used to properly handle the error. This issue has been resolved in the Linux kernel.
Potential Impact
The vulnerability could cause improper lock handling in the kernel, potentially resulting in system instability, crashes, or security issues due to unlocking locks that were never acquired. The CVSS vector indicates high impact on confidentiality, integrity, and availability (C:H/I:H/A:H), but no known exploits are reported in the wild.
Mitigation Recommendations
A fix for this vulnerability has been implemented in the Linux kernel by correcting the error exit path in copy_process() to use the proper label. Users should apply the official kernel updates or patches that include this fix. Since no vendor advisory or patch links are provided here, check the official Linux kernel repositories or vendor advisories for the specific patch and update instructions.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-rgc5-qvp4-69x6
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2025-39976"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a6b72d79c2644c7f847bb25
Added to database: 07/30/2026, 15:50:47 UTC
Last enriched: 07/30/2026, 15:56:04 UTC
Last updated: 09/10/2026, 19:36:50 UTC
Views: 15
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