CVE-2025-39997 | ALSA: usb-audio: fix race condition to UAF in snd_usbmidi_free

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: fix race condition to UAF in snd_usbmidi_free The previous commit 0718a78f6a9f ("ALSA: usb-audio: Kill timer properly at removal") patched a UAF issue caused by the error timer. However, because the error timer kill added in this patch occurs after the endpoint delete, a race condition to UAF still occurs, albeit rarely. Additionally, since kill-cleanup for urb is also missing, freed memory can be accessed in interrupt context related to urb, which can cause UAF. Therefore, to prevent this, error timer and urb must be killed before freeing the heap memory.

Published: 2025-10-15 Last update: 2026-06-01 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2025-39997 is rated Low Risk (3.3/100): low exploitation likelihood (EPSS 0.02%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

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-2025-39997

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 2025-10-15 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-39997

CVSS metrics for this CVE.

No CVSS data in dataset for this CVE.

Weakness enumeration for CVE-2025-39997

GitHub Security Advisory for CVE-2025-39997

GHSA-xc3r-7j5x-74w4 · Severity: unknown — In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: fix race...

OS Trackers for CVE-2025-39997

vendor priority summary link
debian unimportant CVE-2025-39997 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-2025-39997
redhat low https://access.redhat.com/security/cve/CVE-2025-39997
suse medium CVE-2025-39997 severity moderate: SUSE including 505 source package names (13.2-6.19:libjitterentropy3-3.4.1-3.1, 13.2-6.19:libopenssl3-3.1.4-6.1, …), 1183 product×package rows across 240 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (240 product lines)): Fixed 753, Known Affected 231, Known Not Affected 178, First Fixed 21. https://www.suse.com/security/cve/CVE-2025-39997/
ubuntu medium CVE-2025-39997 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1405 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1010, ignored 175, not-affected 122, released 93, needed 3, needs-triage 2. https://ubuntu.com/security/CVE-2025-39997

Affected software / configurations for CVE-2025-39997

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-39997

cvelogic Threat Intelligence