CVE-2026-43459: ASoC: soc-core: flush delayed work before removing DAIs and widgets
In the Linux kernel, the following vulnerability has been resolved:
ASoC: soc-core: flush delayed work before removing DAIs and widgets
When a sound card is unbound while a PCM stream is open, a use-after-free can occur in sndsocdapmstreamevent(), called from the closedelayedwork workqueue handler.
During unbind, sndsocunbindcard() flushes delayed work and then calls soccleanupcardresources(). Inside cleanup, sndcarddisconnectsync() releases all PCM file descriptors, and the resulting PCM close path can call sndsocdapmstreamstop() which schedules new delayed work with a pmdowntime timer delay. Since this happens after the flush in sndsocunbindcard(), the new work is not caught. socremovelinkcomponents() then frees DAPM widgets before this work fires, leading to the use-after-free.
The existing flush in socfreepcmruntime() also cannot help as it runs after socremovelinkcomponents() has already freed the widgets.
Add a flush in soccleanupcardresources() after sndcarddisconnectsync() (after which no new PCM closes can schedule further delayed work) and before socremovelinkdais() and socremovelinkcomponents() (which tear down the structures the delayed work accesses).
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-43459?
CVE-2026-43459 has a high severity rating due to the potential use-after-free vulnerability affecting sound card operations in the Linux kernel.
How do I fix CVE-2026-43459?
To fix CVE-2026-43459, you should update your Linux kernel to the latest version where the vulnerability has been patched.
What software is affected by CVE-2026-43459?
CVE-2026-43459 affects the Linux kernel, particularly in systems utilizing ASoC sound cards.
Is there a workaround for CVE-2026-43459?
Currently, there is no known workaround for CVE-2026-43459, so updating the kernel is the recommended approach.
What type of attack can exploit CVE-2026-43459?
CVE-2026-43459 can be exploited through local attacks that lead to unauthorized access or denial of service when the sound card is improperly managed.