CVE-2025-23134 | ALSA: timer: Don't take register_mutex with copy_from/to_user()

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.

Published: 2025-04-16 Last update: 2025-10-01 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2025-23134 is rated Low Risk (24.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-23134

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-25 0.05% 0.03% -0.02%
2 2026-02-10 0.02% 0.05% +0.03%
3 2025-04-17 0.02%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-23134

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 3.6 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-23134

OS Trackers for CVE-2025-23134

vendor priority summary link
debian unimportant CVE-2025-23134 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-23134
redhat medium https://access.redhat.com/security/cve/CVE-2025-23134
suse medium CVE-2025-23134 severity moderate: SUSE including 88 source package names (15.7.20.5.1:kernel-default-6.4.0-150700.53.3.1, cluster-md-kmp-default, …), 411 product×package rows across 97 product lines (Container suse/hpc/warewulf4-x86_64/sle-hpc-node, Image SLES15-SP7-Azure-3P, … (97 product lines)): Known Not Affected 248, Fixed 163. https://www.suse.com/security/cve/CVE-2025-23134/
ubuntu medium CVE-2025-23134 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 147, not-affected 142, released 115, needs-triage 2. https://ubuntu.com/security/CVE-2025-23134

Affected software / configurations for CVE-2025-23134

Vendor Product Version Raw CPE
linux linux_kernel >= 6.9, < 6.12.23 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.13.11 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.14, < 6.14.2 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2025-23134

cvelogic Threat Intelligence