{"id":"CVE-2026-98309","title":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/vc4: Use managed KMS polling to fix UAF on unbind\n\nvc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides\nno matching drm_kms_helper_poll_fini()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/vc4: Use managed KMS polling to fix UAF on unbind\n\nvc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides\nno matching drm_kms_helper_poll_fini(). T…","severity":"medium","vendor":"Linux","product":"Linux","affected":["Linux >= c8b75bca92cbf064b9fa125fc74a85994452e935 < b6beee927e7f4e3142032ff91b2d0417cdddc0f6","Linux >= c8b75bca92cbf064b9fa125fc74a85994452e935 < cf0c4432bda37b02e7d430ff5017228ceb7caf0c","Linux >= c8b75bca92cbf064b9fa125fc74a85994452e935 < ee507691c18f9fee5d4751e295ab9a7ff31d59ae","Linux >= c8b75bca92cbf064b9fa125fc74a85994452e935 < 7f9780df677370a19b4ec9764f13b1b82073e0d9","Linux >= c8b75bca92cbf064b9fa125fc74a85994452e935 < 073a30d75f309812ed61af134f24ffef4107b13a","Linux 4.4"],"published":"2026-10-06","updated":"2026-10-06","sourceUpdated":"2026-10-06T09:18:22.300","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98309","references":[{"url":"https://git.kernel.org/stable/c/073a30d75f309812ed61af134f24ffef4107b13a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7f9780df677370a19b4ec9764f13b1b82073e0d9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b6beee927e7f4e3142032ff91b2d0417cdddc0f6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cf0c4432bda37b02e7d430ff5017228ceb7caf0c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ee507691c18f9fee5d4751e295ab9a7ff31d59ae","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98309.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98309"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2546345"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98309"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98309"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98309.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ingestedAt":"2026-10-06T08:50:17.413Z","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":["CWE-825"],"epss":0.00175,"epssPercentile":0.06994,"slug":"CVE-2026-98309","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ndrm/vc4: Use managed KMS polling to fix UAF on unbind\n\nvc4_kms_load() calls drm_kms_helper_poll_init() but the driver provides\nno matching drm_kms_helper_poll_fini(). The output poll work stays\nscheduled after unbind and runs on the freed drm_device:\n\n  # modprobe vc4; rmmod vc4; sleep 10\n  BUG: KASAN: slab-use-after-free in delayed_work_timer_fn\n  BUG: KASAN: slab-use-after-free in drm_client_dev_hotplug [drm]\n  Workqueue: events output_poll_execute [drm_kms_helper]\n  Allocated by task 171: __devm_drm_dev_alloc\n  Freed by task 262 (rmmod): drm_dev_put / component_del\n\nUse drmm_kms_helper_poll_init() so polling is finalized with the device,\nas other drivers do.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · updated 2026-10-11 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98309.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":219045,"id":"CVE-2026-98309","ts":1791707043004,"field":"cvss","old":null,"new":"5.5"},{"seq":219044,"id":"CVE-2026-98309","ts":1791707043004,"field":"severity","old":"none","new":"medium"}]}