{"id":"CVE-2026-89893","state":"PUBLISHED","title":"media: cx23885: cancel NetUP CI work before teardown","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: cx23885: cancel NetUP CI work before teardown\n\nnetup_ci_exit() frees a netup_ci_state while its work item,\nnetup_read_ci_status(), may still be pending or running on the system\nworkqueue. The worker obtains the state with container_of() and\ndereferences it, so it must not outlive the state.\n\nnetup_ci_init() queues the initial status read, and CI GPIO interrupts\nsubsequently queue the same work from netup_ci_slot_status(). During\nremove, cx23885_finidev() calls free_irq() before the CI device is\nunregistered. free_irq() prevents further IRQ handlers from running,\nbut does not drain work queued previously, so the worker can run after\nnetup_ci_exit() frees the state.\n\nCall cancel_work_sync() before dvb_ca_en50221_release() and kfree().\n\nThis issue was found by an in-house static analysis tool.","publishedAt":"2026-09-16T10:31:55.374Z","updatedAt":"2026-10-19T08:54:26.213Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"aaf76794b870b0f391eff339252a2e2e22f33a4a","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"f7ff5adb63c1b277565afa54ccc0924d841b4a52","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"140ecbcbf978fbe60f83f8d4f8b1199029a5c763","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"ec82b0cf7f75fd95802592dcc9560fc7f529bba4","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"5deec890ecfa04d21cfa9bb9a2fe5e9dc98db5c5","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"bf3f49273d5bf6acbdad18ff44c01ffcf7a7a146","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"99cd62b9b1c818d6d01a87be9a8e5796314150a2","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"4e143d662ca94888b494b2427fc9e34494eb933a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/pci/cx23885/cimax2.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.30","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.30","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/pci/cx23885/cimax2.c"]}],"references":["https://git.kernel.org/stable/c/aaf76794b870b0f391eff339252a2e2e22f33a4a","https://git.kernel.org/stable/c/f7ff5adb63c1b277565afa54ccc0924d841b4a52","https://git.kernel.org/stable/c/140ecbcbf978fbe60f83f8d4f8b1199029a5c763","https://git.kernel.org/stable/c/ec82b0cf7f75fd95802592dcc9560fc7f529bba4","https://git.kernel.org/stable/c/5deec890ecfa04d21cfa9bb9a2fe5e9dc98db5c5","https://git.kernel.org/stable/c/bf3f49273d5bf6acbdad18ff44c01ffcf7a7a146","https://git.kernel.org/stable/c/99cd62b9b1c818d6d01a87be9a8e5796314150a2","https://git.kernel.org/stable/c/4e143d662ca94888b494b2427fc9e34494eb933a"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89893.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89893","state":"PUBLISHED","datePublished":"2026-09-16T10:31:55.374Z","dateUpdated":"2026-10-19T08:54:26.213Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.773Z"},"containers":{"cna":{"title":"media: cx23885: cancel NetUP CI work before teardown","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: cx23885: cancel NetUP CI work before teardown\n\nnetup_ci_exit() frees a netup_ci_state while its work item,\nnetup_read_ci_status(), may still be pending or running on the system\nworkqueue. The worker obtains the state with container_of() and\ndereferences it, so it must not outlive the state.\n\nnetup_ci_init() queues the initial status read, and CI GPIO interrupts\nsubsequently queue the same work from netup_ci_slot_status(). During\nremove, cx23885_finidev() calls free_irq() before the CI device is\nunregistered. free_irq() prevents further IRQ handlers from running,\nbut does not drain work queued previously, so the worker can run after\nnetup_ci_exit() frees the state.\n\nCall cancel_work_sync() before dvb_ca_en50221_release() and kfree().\n\nThis issue was found by an in-house static analysis tool."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"aaf76794b870b0f391eff339252a2e2e22f33a4a","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"f7ff5adb63c1b277565afa54ccc0924d841b4a52","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"140ecbcbf978fbe60f83f8d4f8b1199029a5c763","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"ec82b0cf7f75fd95802592dcc9560fc7f529bba4","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"5deec890ecfa04d21cfa9bb9a2fe5e9dc98db5c5","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"bf3f49273d5bf6acbdad18ff44c01ffcf7a7a146","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"99cd62b9b1c818d6d01a87be9a8e5796314150a2","versionType":"git"},{"version":"c184dcd282337c09695a4c1761d7ac77fdc8fb7d","status":"affected","lessThan":"4e143d662ca94888b494b2427fc9e34494eb933a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/pci/cx23885/cimax2.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.30","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.30","versionType":"semver"},{"version":"5.10.270","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/pci/cx23885/cimax2.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/aaf76794b870b0f391eff339252a2e2e22f33a4a"},{"url":"https://git.kernel.org/stable/c/f7ff5adb63c1b277565afa54ccc0924d841b4a52"},{"url":"https://git.kernel.org/stable/c/140ecbcbf978fbe60f83f8d4f8b1199029a5c763"},{"url":"https://git.kernel.org/stable/c/ec82b0cf7f75fd95802592dcc9560fc7f529bba4"},{"url":"https://git.kernel.org/stable/c/5deec890ecfa04d21cfa9bb9a2fe5e9dc98db5c5"},{"url":"https://git.kernel.org/stable/c/bf3f49273d5bf6acbdad18ff44c01ffcf7a7a146"},{"url":"https://git.kernel.org/stable/c/99cd62b9b1c818d6d01a87be9a8e5796314150a2"},{"url":"https://git.kernel.org/stable/c/4e143d662ca94888b494b2427fc9e34494eb933a"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The use-after-free is reached only on local PCI teardown of the NetUP Dual DVB-S2 CI card (cx23885_finidev → cx23885_dvb_unregister → netup_ci_exit) via sysfs unbind/remove, rmmod, or local PCI hot-remove. No network, adjacent-network, or remote-peer path queues netup_read_ci_status or frees netup_ci_state.\nAC:L - netup_ci_init() unconditionally schedule_work()s the status worker, and CAM GPIO IRQs re-queue it via netup_ci_slot_status(); an attacker who then unbinds/rebinds controls both sides of the missing cancel_work_sync race. The worker's 33-byte I2C transfer widens a retryable window, so this UAF is Low complexity.\nPR:L - Per CNA driver-removal UAF precedent on this same NetUP PCIe DVB family (CVE-2023-53219), an unprivileged local video-group/uaccess user on broadcast, HTPC, or set-top systems can spray the freed netup_ci_state while teardown proceeds. Init-namespace root is not required for the UAF itself.\nUI:N - The attacker queues the CI work (driver bind or CAM GPIO) and initiates PCI unbind, rmmod, or hot-remove themselves. No separate victim action such as mounting a filesystem or opening attacker-supplied content is required.\nS:U - The use-after-free corrupts the host kernel netup_ci_state heap object and dvb_ca_en50221 private state within the same security authority. It is not a VM escape, IOMMU/DMA isolation bypass, or sandbox breakout.\nC:H - After kfree(state), netup_read_ci_status recovers the object via container_of() and reads state->ca, i2c_adap, and status from freed memory. Spraying the slab turns this kernel heap UAF into an arbitrary read, which per UAF guidance is Confidentiality High.\nI:H - The dangling worker writes state->status/next_status_checked_time and calls dvb_ca_en50221_frda_irq(), which loads ca->pub->read_cam_control from the freed object, a heap-spray function-pointer hijack. UAF memory corruption is scored Integrity High.\nA:H - Use-after-free of netup_ci_state from workqueue context after kfree, or a NULL deref of ca->private if the worker interleaves dvb_ca_en50221_release, oopses or panics the kernel even when not fully exploited, so availability impact is High."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:54:26.213Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.30","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}