CVE-2026-89940 (GCVE-0-2026-89940)
Vulnerability from cvelistv5 – Published: 2026-09-16 10:32 – Updated: 2026-09-16 14:40
VLAI
EPSS
VEX
Title
iio: buffer: Tie IIO dma fence lock lifetime to the fence
Summary
In the Linux kernel, the following vulnerability has been resolved:
iio: buffer: Tie IIO dma fence lock lifetime to the fence
The `iio_dma_fence` implementation currently uses a lock embedded in the
`iio_dmabuf_priv`. But the `iio_dma_fence` can outlive the
`iio_dmabuf_priv`, which can cause a use-after-free.
Tie the lifetime of the lock to the lifetime of the fence by embedding them
in the same struct.
We can't just hold a reference to the `iio_dmabuf_priv` from the
`iio_dma_fence` since `iio_buffer_dmabuf_release()` might sleep and the
fence release callback is not allowed to sleep.
Note that the `dma_fence` framework now has an internal lock that gets used
when the passing `NULL` for `lock` in `dma_fence_init()`, but in order to
allow this patch to be backportable use an external lock.
Severity
7.8 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f , < 6865d79fca17a80fbd60c12550ca9a5e0e20e0eb
(git)
Affected: 3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f , < 510497e31be4f241103507315a859e2085ccb081 (git) Affected: 3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f , < 8b3e221590181a8beb3735bbabf166df02c839b5 (git) Affected: 3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f , < f25ec4627d935dedfb5fe83bd2c2678cdcc19611 (git) |
guessed | |
| Linux | Linux |
Affected:
6.11
Unaffected: 0 , < 6.11 (semver) Unaffected: 6.12.110 , ≤ 6.12.* (semver) Unaffected: 6.18.51 , ≤ 6.18.* (semver) Unaffected: 7.2.5 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"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-rc1",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.110",
"versionStartIncluding": "6.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.51",
"versionStartIncluding": "6.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2.5",
"versionStartIncluding": "6.11",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.3-rc1",
"versionStartIncluding": "6.11",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"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\u0027t 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": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"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\u0027s 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."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-16T14:40:26.549Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"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"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-89940",
"datePublished": "2026-09-16T10:32:28.395Z",
"dateReserved": "2026-09-11T19:38:34.776Z",
"dateUpdated": "2026-09-16T14:40:26.549Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"nvd": "{\"cve\":{\"id\":\"CVE-2026-89940\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-09-16T11:17:03.610\",\"lastModified\":\"2026-09-16T15:18:19.340\",\"vulnStatus\":\"Received\",\"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\u0027t 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.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/iio/industrialio-buffer.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f\",\"lessThan\":\"6865d79fca17a80fbd60c12550ca9a5e0e20e0eb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f\",\"lessThan\":\"510497e31be4f241103507315a859e2085ccb081\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f\",\"lessThan\":\"8b3e221590181a8beb3735bbabf166df02c839b5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"3e26d9f08fbe0b73e951a5e810fdb7a332b7e37f\",\"lessThan\":\"f25ec4627d935dedfb5fe83bd2c2678cdcc19611\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/iio/industrialio-buffer.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.11\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.11\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.110\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.51\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2.5\",\"lessThanOrEqual\":\"7.2.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.3-rc1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"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\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"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\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…