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Vulnerability · Published Oct 15, 2025 · Assigned by Linux

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

Unrated

In plain English

A security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS )–Not rated
Exploit odds (30 days)0.2%top 88.6% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.176-1DEBIAN-CVE-2025-39997
Debian:14linux6.16.11-1DEBIAN-CVE-2025-39997
Ubuntu:25.10linux6.17.0-6.6UBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-aws6.17.0-1003.3UBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-azure6.17.0-1006.6UBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-azure-fdeno fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-gcp6.17.0-1003.3UBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-oracle6.17.0-1003.3UBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-raspi6.17.0-1004.4UBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-realtime6.17.0-1002.3UBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2025-39997
Ubuntu:25.10linux-riscv6.17.0-6.6.1UBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2025-39997
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2025-39997

Affected products (as reported)

VendorProductVersions
Linux Linux 06513dd6d32c37d0364db8488cfdf3e14da238a8 – before e63f049c7764b615d1d50cb486745fa63372b42defaf61052b8ff9ee8968912fbaf02c2847c78ede – before e16985513e89466a236d2a7c202783b4dd0c5a46647410a7da46067953a53c0d03f8680eff570959 – before dc4874366cf6cf4a31d8fa4b7f0e2a5b2d7647bac611b9e55174e439dcd85a72969b43a95f3827a4 – before 647d6b8d22be12842fde6ed0c56859ebc615f21e0718a78f6a9f04b88d0dc9616cc216b31c5f3cf1 – before af600e7f5526d16146b3ae99f6ad57bfea79ca330718a78f6a9f04b88d0dc9616cc216b31c5f3cf1 – before 353d8c715cc951a980728133c9dd64ca5a0a186c0718a78f6a9f04b88d0dc9616cc216b31c5f3cf1 – before 9f2c0ac1423d5f267e7f1d1940780fc764b0fee362066758d2ae169278e5d6aea5995b1b6f6ddeb5
Linux Linux 6.16

References