How severe is CVE-2025-23134?

CVE-2025-23134 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-23134 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-23134?

CVE-2025-23134 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-23134?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-23134 have an EU (EUVD) identifier?

Yes. CVE-2025-23134 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11166.

When was CVE-2025-23134 published?

CVE-2025-23134 was published on 2025-04-16 and last updated on 2026-06-17.

CVE-2025-23134

CVE-2025-23134 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-667.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-11166
Weakness: CWE-667
Affected product: Linux Linux Kernel
Published: 2025-04-16
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Don't take register_mutex with copy_from/to_user() The infamous mmap_lock taken in copy_from/to_user() can be often problematic when it's called inside another mutex, as they might lead to deadlocks. In the case of ALSA timer code, the bad pattern is with guard(mutex)(&register_mutex) that covers copy_from/to_user() -- which was mistakenly introduced at converting to guard(), and it had been carefully worked around in the past. This patch fixes those pieces simply by moving copy_from/to_user() out of the register mutex lock again.

Frequently asked questions

What is CVE-2025-23134?: In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Don't take register_mutex with copy_from/to_user() The infamous mmap_lock taken in copy_from/to_user() can be often problematic when it's called inside another mutex, as they might lead to deadlocks. In the case of ALSA timer code, the bad pattern is with guard(mutex)(&register_mutex) that covers copy_from/to_user() -- which was mistakenly introduced at converting to guard(), and it had been carefully worked around in the past. This patch fixes those pieces simply by moving copy_from/to_user() out of the register mutex lock again.
How severe is CVE-2025-23134?: CVE-2025-23134 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-23134 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-23134?: CVE-2025-23134 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-23134?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-23134 have an EU (EUVD) identifier?: Yes. CVE-2025-23134 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11166.
When was CVE-2025-23134 published?: CVE-2025-23134 was published on 2025-04-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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