CVE-2025-71180

Published Jan 31, 2026

Last updated 5 months ago

CVSS medium 5.5

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-71180 describes a vulnerability found within the Linux kernel, specifically affecting the `counter: interrupt-cnt` component. The issue stems from an improper handling of the `IRQF_NO_THREAD` flag in interrupt request (IRQ) handlers. This can lead to an "Invalid wait context" bug, which is detected by `CONFIG_PROVE_RAW_LOCK_NESTING` when a process attempts to acquire a lock, such as `counter->events_list_lock`, in an inappropriate context. The resolution for this vulnerability involves removing the `IRQF_NO_THREAD` flag. This approach was chosen over switching to `raw_spinlock_t`, as the latter would restrict all potential nested locks to `raw_spinlock_t` only. The vulnerability impacts various versions of the Linux kernel, with specific affected ranges identified by commit hashes.

Description
In the Linux kernel, the following vulnerability has been resolved: counter: interrupt-cnt: Drop IRQF_NO_THREAD flag An IRQ handler can either be IRQF_NO_THREAD or acquire spinlock_t, as CONFIG_PROVE_RAW_LOCK_NESTING warns: ============================= [ BUG: Invalid wait context ] 6.18.0-rc1+git... #1 ----------------------------- some-user-space-process/1251 is trying to lock: (&counter->events_list_lock){....}-{3:3}, at: counter_push_event [counter] other info that might help us debug this: context-{2:2} no locks held by some-user-space-process/.... stack backtrace: CPU: 0 UID: 0 PID: 1251 Comm: some-user-space-process 6.18.0-rc1+git... #1 PREEMPT Call trace: show_stack (C) dump_stack_lvl dump_stack __lock_acquire lock_acquire _raw_spin_lock_irqsave counter_push_event [counter] interrupt_cnt_isr [interrupt_cnt] __handle_irq_event_percpu handle_irq_event handle_simple_irq handle_irq_desc generic_handle_domain_irq gpio_irq_handler handle_irq_desc generic_handle_domain_irq gic_handle_irq call_on_irq_stack do_interrupt_handler el0_interrupt __el0_irq_handler_common el0t_64_irq_handler el0t_64_irq ... and Sebastian correctly points out. Remove IRQF_NO_THREAD as an alternative to switching to raw_spinlock_t, because the latter would limit all potential nested locks to raw_spinlock_t only.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

  1. CVE-2025-71180 In the Linux kernel, the following vulnerability has been resolved: counter https://t.co/A3lhJ9iEOc

    @VulmonFeeds

    31 Jan 2026

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  2. A severe vulnerability was disclosed for Linux Kernel (CVE-2025-71180) https://t.co/XvFZ5QUCYn

    @vuldb

    31 Jan 2026

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  3. CVE-2025-71180 In the Linux kernel, the following vulnerability has been resolved: counter: interrupt-cnt: Drop IRQF_NO_THREAD flag An IRQ handler can either be IRQF_NO_THREAD or … https://t.co/YtFtiaz3fv

    @CVEnew

    31 Jan 2026

    700 Impressions

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Configurations

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References

Sources include official advisories and independent security research.