CVE-2025-39745

MEDIUM EPSS 4.0%
Published Sep 11, 20259mo ago · Modified Jun 17, 20262w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Sep 11, 2025 9mo ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: rcutorture: Fix rcutorture_one_extend_check() splat in RT kernels For built with CONFIG_PREEMPT_RT=y kernels, running rcutorture tests resulted in the following splat: [ 68.797425] rcutorture_one_extend_check during change: Current 0x1 To add 0x1 To remove 0x0 preempt_count() 0x0 [ 68.797533] WARNING: CPU: 2 PID: 512 at kernel/rcu/rcutorture.c:1993 rcutorture_one_extend_check+0x419/0x560 [rcutorture] [ 68.797601] Call Trace: [ 68.797602] <TASK> [ 68.797619] ? lockdep_softirqs_off+0xa5/0x160 [ 68.797631] rcutorture_one_extend+0x18e/0xcc0 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797646] ? local_clock+0x19/0x40 [ 68.797659] rcu_torture_one_read+0xf0/0x280 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797678] ? __pfx_rcu_torture_one_read+0x10/0x10 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797804] ? __pfx_rcu_torture_timer+0x10/0x10 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797815] rcu-torture: rcu_torture_reader task started [ 68.797824] rcu-torture: Creating rcu_torture_reader task [ 68.797824] rcu_torture_reader+0x238/0x580 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c] [ 68.797836] ? kvm_sched_clock_read+0x15/0x30 Disable BH does not change the SOFTIRQ corresponding bits in preempt_count() for RT kernels, this commit therefore use softirq_count() to check the if BH is disabled.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
4.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 2

VendorProductVersionRange
linuxlinux_kernel* <6.15.11
linuxlinux_kernel*≥6.16  –  <6.16.2

References 3

  • git.kernel.org https://git.kernel.org/stable/c/69c5ae0f441c2d72e8f48dc1e08464c172360c4c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8d71351d88e478d3c4e945e3218e97ec677fd807
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a85550267247cdf5e7499be00ea8e388ab014e50
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/69c5ae0f441c2d72e8f48dc1e08464c172360c4c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8d71351d88e478d3c4e945e3218e97ec677fd807
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a85550267247cdf5e7499be00ea8e388ab014e50
    Patch