{"api_version":"1","generated_at":"2026-09-12T02:59:53+00:00","cve":"CVE-2026-89738","urls":{"html":"https://cve.report/CVE-2026-89738","api":"https://cve.report/api/cve/CVE-2026-89738.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89738","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89738"},"summary":{"title":"usb: gadget: at91_udc: drain polled-VBUS timer/work before udc is freed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: at91_udc: drain polled-VBUS timer/work before udc is freed\n\nIn polled-VBUS mode (board.vbus_pin && board.vbus_polled), probe arms a\nself-restarting cycle: at91_vbus_timer() schedules vbus_timer_work, and\nat91_vbus_timer_work() calls at91_vbus_update() and re-arms the timer via\nmod_timer(). Both recover the same udc through container_of and dereference\nit on every iteration.\n\nNeither teardown path cancels this cycle. udc is devm-allocated, so it is\nfreed after at91udc_remove() returns, and is likewise freed when probe\nfails and devres runs. A timer callback or work item that is pending or\nrunning at either point dereferences the freed udc.\n\nAdd at91_udc_shutdown_vbus_timer() and call it from at91udc_remove() and\nfrom the usb_add_gadget_udc() failure path in probe; the remaining probe\nerror paths fail before the timer is armed. timer_shutdown_sync() waits\nfor a running callback and clears timer->function, which makes the work\nhandler's mod_timer() a permanent no-op; cancel_work_sync() then drains\nany pending or running work whose re-arm attempt now does nothing. The\ntimer must be shut down first, since cancelling the work alone would let\nthe timer re-queue it. The guard mirrors probe: in IRQ mode the timer and\nwork_struct are never initialized.\n\nThis does not require a fault; a normal driver unbind can interleave with\nan already queued work item.\n\nThis issue was found by an in-house static analysis tool.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-11 20:20:04","updated_at":"2026-09-11 20:20:04"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/557ef547d49ff5e6026a4d39bdd3113bd81d7688","name":"https://git.kernel.org/stable/c/557ef547d49ff5e6026a4d39bdd3113bd81d7688","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/51a311eb97e91ce1aed3005cb71ccb2e30f8cce8","name":"https://git.kernel.org/stable/c/51a311eb97e91ce1aed3005cb71ccb2e30f8cce8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a2a602cb1e28d76a5398cec3fa21b0110385f501","name":"https://git.kernel.org/stable/c/a2a602cb1e28d76a5398cec3fa21b0110385f501","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c27d13ce4bab80fbdf6523928071b6c24b37606c","name":"https://git.kernel.org/stable/c/c27d13ce4bab80fbdf6523928071b6c24b37606c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89738","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89738","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4037242c4f5ff77afe61bf07ca1e8a99490219e5 a2a602cb1e28d76a5398cec3fa21b0110385f501 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4037242c4f5ff77afe61bf07ca1e8a99490219e5 51a311eb97e91ce1aed3005cb71ccb2e30f8cce8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4037242c4f5ff77afe61bf07ca1e8a99490219e5 557ef547d49ff5e6026a4d39bdd3113bd81d7688 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4037242c4f5ff77afe61bf07ca1e8a99490219e5 c27d13ce4bab80fbdf6523928071b6c24b37606c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.36","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.36 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.109 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.50 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/usb/gadget/udc/at91_udc.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"a2a602cb1e28d76a5398cec3fa21b0110385f501","status":"affected","version":"4037242c4f5ff77afe61bf07ca1e8a99490219e5","versionType":"git"},{"lessThan":"51a311eb97e91ce1aed3005cb71ccb2e30f8cce8","status":"affected","version":"4037242c4f5ff77afe61bf07ca1e8a99490219e5","versionType":"git"},{"lessThan":"557ef547d49ff5e6026a4d39bdd3113bd81d7688","status":"affected","version":"4037242c4f5ff77afe61bf07ca1e8a99490219e5","versionType":"git"},{"lessThan":"c27d13ce4bab80fbdf6523928071b6c24b37606c","status":"affected","version":"4037242c4f5ff77afe61bf07ca1e8a99490219e5","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/usb/gadget/udc/at91_udc.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.36"},{"lessThan":"2.6.36","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.109","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.50","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.109","versionStartIncluding":"2.6.36","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.50","versionStartIncluding":"2.6.36","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"2.6.36","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"2.6.36","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: at91_udc: drain polled-VBUS timer/work before udc is freed\n\nIn polled-VBUS mode (board.vbus_pin && board.vbus_polled), probe arms a\nself-restarting cycle: at91_vbus_timer() schedules vbus_timer_work, and\nat91_vbus_timer_work() calls at91_vbus_update() and re-arms the timer via\nmod_timer(). Both recover the same udc through container_of and dereference\nit on every iteration.\n\nNeither teardown path cancels this cycle. udc is devm-allocated, so it is\nfreed after at91udc_remove() returns, and is likewise freed when probe\nfails and devres runs. A timer callback or work item that is pending or\nrunning at either point dereferences the freed udc.\n\nAdd at91_udc_shutdown_vbus_timer() and call it from at91udc_remove() and\nfrom the usb_add_gadget_udc() failure path in probe; the remaining probe\nerror paths fail before the timer is armed. timer_shutdown_sync() waits\nfor a running callback and clears timer->function, which makes the work\nhandler's mod_timer() a permanent no-op; cancel_work_sync() then drains\nany pending or running work whose re-arm attempt now does nothing. The\ntimer must be shut down first, since cancelling the work alone would let\nthe timer re-queue it. The guard mirrors probe: in IRQ mode the timer and\nwork_struct are never initialized.\n\nThis does not require a fault; a normal driver unbind can interleave with\nan already queued work item.\n\nThis issue was found by an in-house static analysis tool."}],"providerMetadata":{"dateUpdated":"2026-09-11T19:46:45.898Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/a2a602cb1e28d76a5398cec3fa21b0110385f501"},{"url":"https://git.kernel.org/stable/c/51a311eb97e91ce1aed3005cb71ccb2e30f8cce8"},{"url":"https://git.kernel.org/stable/c/557ef547d49ff5e6026a4d39bdd3113bd81d7688"},{"url":"https://git.kernel.org/stable/c/c27d13ce4bab80fbdf6523928071b6c24b37606c"}],"title":"usb: gadget: at91_udc: drain polled-VBUS timer/work before udc is freed","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89738","datePublished":"2026-09-11T19:46:45.898Z","dateReserved":"2026-09-11T19:38:34.761Z","dateUpdated":"2026-09-11T19:46:45.898Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-11 20:20:04","lastModifiedDate":"2026-09-11 20:20:04","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89738","Ordinal":"1","Title":"usb: gadget: at91_udc: drain polled-VBUS timer/work before udc i","CVE":"CVE-2026-89738","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89738","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: at91_udc: drain polled-VBUS timer/work before udc is freed\n\nIn polled-VBUS mode (board.vbus_pin && board.vbus_polled), probe arms a\nself-restarting cycle: at91_vbus_timer() schedules vbus_timer_work, and\nat91_vbus_timer_work() calls at91_vbus_update() and re-arms the timer via\nmod_timer(). Both recover the same udc through container_of and dereference\nit on every iteration.\n\nNeither teardown path cancels this cycle. udc is devm-allocated, so it is\nfreed after at91udc_remove() returns, and is likewise freed when probe\nfails and devres runs. A timer callback or work item that is pending or\nrunning at either point dereferences the freed udc.\n\nAdd at91_udc_shutdown_vbus_timer() and call it from at91udc_remove() and\nfrom the usb_add_gadget_udc() failure path in probe; the remaining probe\nerror paths fail before the timer is armed. timer_shutdown_sync() waits\nfor a running callback and clears timer->function, which makes the work\nhandler's mod_timer() a permanent no-op; cancel_work_sync() then drains\nany pending or running work whose re-arm attempt now does nothing. The\ntimer must be shut down first, since cancelling the work alone would let\nthe timer re-queue it. The guard mirrors probe: in IRQ mode the timer and\nwork_struct are never initialized.\n\nThis does not require a fault; a normal driver unbind can interleave with\nan already queued work item.\n\nThis issue was found by an in-house static analysis tool.","Type":"Description","Title":"usb: gadget: at91_udc: drain polled-VBUS timer/work before udc i"}]}}}