Use-after-free in Linux kernel - CVE-2026-64029
Published: July 20, 2026
Vulnerability identifier: #VU138625
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-64029
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in seq_ump_process_event() and snd_rawmidi_kernel_write1() when processing sequencer events during concurrent output teardown. A local user can trigger concurrent event delivery and output close operations to cause a denial of service.
The issue arises from a race condition between the event_input path and the last output unuse path, where the rawmidi substream runtime may be freed while still in use.
How to mitigate CVE-2026-64029
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/0cb1ad795570167558530d6194297ac2396a1991
- https://git.kernel.org/stable/c/3aab4a58d23fb22dac5b558bbe5df1a8dad00b4b
- https://git.kernel.org/stable/c/60a1969fae6209644698fca91c185d153674f631
- https://git.kernel.org/stable/c/8ba1c4ddbb1c67d34bb440aecb9f5690ed3f64cb
- https://git.kernel.org/stable/c/ef46b616a4c219185bbf10ebcbacb571583fd0e4