CVE-2026-89940

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89940", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.776Z", "datePublished": "2026-09-16T10:32:28.395Z", "dateUpdated": "2026-10-19T08:55:14.651Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:55:14.651Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niio: buffer: Tie IIO dma fence lock lifetime to the fence\n\nThe `iio_dma_fence` implementation currently uses a lock embedded in the\n`iio_dmabuf_priv`. But the `iio_dma_fence` can outlive the\n`iio_dmabuf_priv`, which can cause a use-after-free.\n\nTie the lifetime of the lock to the lifetime of the fence by embedding them\nin the same struct.\n\nWe can't just hold a reference to the `iio_dmabuf_priv` from the\n`iio_dma_fence` since `iio_buffer_dmabuf_release()` might sleep and the\nfence release callback is not allowed to sleep.\n\nNote that the `dma_fence` framework now has an internal lock that gets used\nwhen the passing `NULL` for `lock` in `dma_fence_init()`, but in order to\nallow this patch to be backportable use an external lock."}], "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 through local IIO_BUFFER_DMABUF_ATTACH/ENQUEUE/DETACH ioctls on an anonymous iio:buffer fd from IIO_BUFFER_GET_FD_IOCTL on /dev/iio:deviceN; it is not reachable from network packet processing or adjacent-link protocols.\nAC:L - The attacker fully controls the lifetime mismatch: they attach and enqueue a DMA-BUF so the dma_fence lock lives in iio_dmabuf_priv, then detach so priv is freed while the fence remains in the DMA-BUF reservation, and later DMA_BUF_IOCTL_SYNC/wait takes that freed lock.\nPR:L - The IIO open and ioctl path has no capability check, only filesystem access to the device node. On Android phones, industrial converters, and embedded systems exposing this DMA-BUF buffer API, /dev/iio:device* is commonly group-accessible without init-namespace root.\nUI:N - The attacker opens the IIO device, issues the DMA-BUF attach/enqueue/detach ioctls, and waits on their own DMA-BUF file descriptor; no separate victim action is required.\nS:U - This is a standard in-kernel heap use-after-free of iio_dmabuf_priv within the host kernel's security authority, not a VM escape, IOMMU boundary bypass, or sandbox escape.\nC:H - The dma_fence retains a pointer to a spinlock embedded in freed iio_dmabuf_priv; later fence wait/sync operations use that lock, a slab use-after-free that can be turned into an arbitrary kernel memory read via heap spraying.\nI:H - The same use-after-free of iio_dmabuf_priv lets an attacker reclaim the object and corrupt dma_fence lock and callback state during later wait or signaling paths, enabling heap corruption, arbitrary write, and control-flow hijacking.\nA:H - Taking a spinlock in already-freed iio_dmabuf_priv memory causes a kernel oops, BUG, or panic; any use-after-free is high availability impact even when not fully exploited."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/iio/industrialio-buffer.c"], "versions": [{"version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "lessThan": "6865d79fca17a80fbd60c12550ca9a5e0e20e0eb", "status": "affected", "versionType": "git"}, {"version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "lessThan": "510497e31be4f241103507315a859e2085ccb081", "status": "affected", "versionType": "git"}, {"version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "lessThan": "8b3e221590181a8beb3735bbabf166df02c839b5", "status": "affected", "versionType": "git"}, {"version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "lessThan": "f25ec4627d935dedfb5fe83bd2c2678cdcc19611", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/iio/industrialio-buffer.c"], "versions": [{"version": "6.11", "status": "affected"}, {"version": "0", "lessThan": "6.11", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.5", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.12.110"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.18.51"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "7.2.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/6865d79fca17a80fbd60c12550ca9a5e0e20e0eb"}, {"url": "https://git.kernel.org/stable/c/510497e31be4f241103507315a859e2085ccb081"}, {"url": "https://git.kernel.org/stable/c/8b3e221590181a8beb3735bbabf166df02c839b5"}, {"url": "https://git.kernel.org/stable/c/f25ec4627d935dedfb5fe83bd2c2678cdcc19611"}], "title": "iio: buffer: Tie IIO dma fence lock lifetime to the fence", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/iio/industrialio-buffer.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6865d79fca17a80fbd60c12550ca9a5e0e20e0eb", "status": "affected", "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "versionType": "git"}, {"lessThan": "510497e31be4f241103507315a859e2085ccb081", "status": "affected", "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "versionType": "git"}, {"lessThan": "8b3e221590181a8beb3735bbabf166df02c839b5", "status": "affected", "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "versionType": "git"}, {"lessThan": "f25ec4627d935dedfb5fe83bd2c2678cdcc19611", "status": "affected", "version": "3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/iio/industrialio-buffer.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.11"}, {"lessThan": "6.11", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.110", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.51", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niio: buffer: Tie IIO dma fence lock lifetime to the fence\n\nThe `iio_dma_fence` implementation currently uses a lock embedded in the\n`iio_dmabuf_priv`. But the `iio_dma_fence` can outlive the\n`iio_dmabuf_priv`, which can cause a use-after-free.\n\nTie the lifetime of the lock to the lifetime of the fence by embedding them\nin the same struct.\n\nWe can't just hold a reference to the `iio_dmabuf_priv` from the\n`iio_dma_fence` since `iio_buffer_dmabuf_release()` might sleep and the\nfence release callback is not allowed to sleep.\n\nNote that the `dma_fence` framework now has an internal lock that gets used\nwhen the passing `NULL` for `lock` in `dma_fence_init()`, but in order to\nallow this patch to be backportable use an external lock."}], "id": "CVE-2026-89940", "lastModified": "2026-10-19T09:18:39.800", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-09-16T11:17:03.610", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/510497e31be4f241103507315a859e2085ccb081"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6865d79fca17a80fbd60c12550ca9a5e0e20e0eb"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8b3e221590181a8beb3735bbabf166df02c839b5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f25ec4627d935dedfb5fe83bd2c2678cdcc19611"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f,6865d79fca17a80fbd60c12550ca9a5e0e20e0eb)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f,510497e31be4f241103507315a859e2085ccb081)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f,8b3e221590181a8beb3735bbabf166df02c839b5)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f,f25ec4627d935dedfb5fe83bd2c2678cdcc19611)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "6.11"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.11)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.110,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.51,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.5,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-18T08:15:06.138899+00:00", "updated": "2026-09-18T22:30:15.484906+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-416"]}