CVE-2026-98309
In the Linux kernel, the following vulnerability has been resolved: drm/vc4: Use managed KMS polling to fix UAF on unbind vc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides no matching drm_kms_helper_poll_fini(). The output poll work stays scheduled after unbind and runs on the freed drm_device: # modprobe vc4; rmmod vc4; sleep 10 BUG: KASAN: slab-use-after-free in delayed_work_timer_fn BUG: KASAN: slab-use-after-free in drm_client_dev_hotplug [drm] Workqueue: events output_poll_execute [drm_kms_helper] Allocated by task 171: __devm_drm_dev_alloc Freed by task 262 (rmmod): drm_dev_put / component_del Use drmm_kms_helper_poll_init() so polling is finalized with the device, as other drivers do.
Affected versions
Linux kernel versions
4.4
and later are affected. Fixed in
6.6.158,
6.12.112,
6.18.54,
7.2.8,
7.3-rc4
and their respective stable series.
References
5 totalFrequently asked questions
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What is CVE-2026-98309?
CVE-2026-98309 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 4.4 onward and has been patched in 6.6.158, 6.12.112, 6.18.54 and others. CVE-2026-98309 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-98309?
Yes. CVE-2026-98309 has been patched. Fixed versions include 6.6.158, 6.12.112, 6.18.54 and others. If you are running Linux kernel 4.4 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-98309 actively exploited?
No. CVE-2026-98309 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.