CVE-2026-63853 (GCVE-0-2026-63853)
Vulnerability from cvelistv5 – Published: 2026-07-19 14:04 – Updated: 2026-08-05 12:36
VLAI
EPSS
VEX
Title
drm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring
Summary
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring
VCN encoder and decoder rings do not support 64-bit user fence writes,
reject CS submissions with user fences.
(cherry picked from commit fd852c048b46f9825e904a4f3f4538fe9d8827d9)
Severity
7.8 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
8da1170a16e4d4b49fa07d1f75ad480847ff7eca , < 1286b6872de0aee1feeeaa6dbac86369806de9a5
(git)
Affected: 8da1170a16e4d4b49fa07d1f75ad480847ff7eca , < 6bdd2ed6458d35c368fbe9550a4d7f342abd3a92 (git) Affected: 8da1170a16e4d4b49fa07d1f75ad480847ff7eca , < 51f694221047c84fa185be98210eb2c354ffb8c6 (git) |
guessed | |
| Linux | Linux |
Affected:
5.19
Unaffected: 0 , < 5.19 (semver) Unaffected: 6.18.33 , ≤ 6.18.* (semver) Unaffected: 7.0.10 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "1286b6872de0aee1feeeaa6dbac86369806de9a5",
"status": "affected",
"version": "8da1170a16e4d4b49fa07d1f75ad480847ff7eca",
"versionType": "git"
},
{
"lessThan": "6bdd2ed6458d35c368fbe9550a4d7f342abd3a92",
"status": "affected",
"version": "8da1170a16e4d4b49fa07d1f75ad480847ff7eca",
"versionType": "git"
},
{
"lessThan": "51f694221047c84fa185be98210eb2c354ffb8c6",
"status": "affected",
"version": "8da1170a16e4d4b49fa07d1f75ad480847ff7eca",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.19"
},
{
"lessThan": "5.19",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.33",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.10",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.33",
"versionStartIncluding": "5.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.0.10",
"versionStartIncluding": "5.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1",
"versionStartIncluding": "5.19",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring\n\nVCN encoder and decoder rings do not support 64-bit user fence writes,\nreject CS submissions with user fences.\n\n(cherry picked from commit fd852c048b46f9825e904a4f3f4538fe9d8827d9)"
}
],
"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 - Exploitation requires submitting a crafted AMDGPU command stream through DRM_IOCTL_AMDGPU_CS on a local /dev/dri/renderD* device; there is no network, adjacent-radio, or physical-access path to the vulnerable VCN v4.0 unified encoder ring handling.\nAC:L - An attacker with render-node access can deterministically submit a CS containing an AMDGPU_CHUNK_ID_FENCE chunk targeting the VCN encoder ring; no race, special timing, or victim state beyond having a VCN 4.0-capable AMDGPU is required.\nPR:L - The path is reachable by any local user who can open the DRM render node (typically membership in the render/video group on desktops, workstations, and cloud GPU VMs); it does not require real root in the init namespace.\nUI:N - Triggering the bug is fully programmatic via ioctl-based CS submission and does not require any victim to open files, mount filesystems, or perform other interactive actions.\nS:U - Impact is confined to the AMDGPU/VCN driver and GPU resources of the submitting security context; it does not cross a VM, container, or IOMMU security boundary to affect a different authority.\nC:H - Without the no_user_fence guard, amdgpu_ib_commit emits a 64-bit user fence (AMDGPU_FENCE_FLAG_64BIT) on a ring whose emit_fence path only supports 32-bit fence writes, causing the VCN hardware to perform an unvalidated GPU DMA write that can corrupt adjacent GPU-mapped memory and be leveraged for information disclosure.\nI:H - The same rogue GPU-initiated fence write is a memory-corruption primitive that can modify GPU-accessible buffers (including shared dma-buf mappings) outside the intended 8-byte fence field, enabling integrity violations and potential further exploitation.\nA:H - Malformed fence/trap commands on the VCN unified encoder ring can hang or fault the VCN block and force GPU/driver reset, denying graphics and compute availability to all users of the device on shared workstations and servers."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T12:36:31.693Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/1286b6872de0aee1feeeaa6dbac86369806de9a5"
},
{
"url": "https://git.kernel.org/stable/c/6bdd2ed6458d35c368fbe9550a4d7f342abd3a92"
},
{
"url": "https://git.kernel.org/stable/c/51f694221047c84fa185be98210eb2c354ffb8c6"
}
],
"title": "drm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-63853",
"datePublished": "2026-07-19T14:04:43.885Z",
"dateReserved": "2026-07-19T07:54:57.016Z",
"dateUpdated": "2026-08-05T12:36:31.693Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-63853",
"date": "2026-09-23",
"epss": "0.0013",
"percentile": "0.03036"
},
"microsoft_vex": {
"current_release_date": "2026-09-23T02:49:44.000Z",
"cve": "CVE-2026-63853",
"id": "msrc_CVE-2026-63853",
"initial_release_date": "2026-07-20T01:01:55.000Z",
"product_status:known_affected": "3",
"source": "Microsoft CSAF VEX",
"status": "final",
"title": "drm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring",
"url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-63853.json",
"version": "4"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "1286b6872de0aee1feeeaa6dbac86369806de9a5",
"status": "affected",
"version": "8da1170a16e4d4b49fa07d1f75ad480847ff7eca",
"versionType": "git"
},
{
"lessThan": "6bdd2ed6458d35c368fbe9550a4d7f342abd3a92",
"status": "affected",
"version": "8da1170a16e4d4b49fa07d1f75ad480847ff7eca",
"versionType": "git"
},
{
"lessThan": "51f694221047c84fa185be98210eb2c354ffb8c6",
"status": "affected",
"version": "8da1170a16e4d4b49fa07d1f75ad480847ff7eca",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.19"
},
{
"lessThan": "5.19",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.33",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.10",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.1",
"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\ndrm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring\n\nVCN encoder and decoder rings do not support 64-bit user fence writes,\nreject CS submissions with user fences.\n\n(cherry picked from commit fd852c048b46f9825e904a4f3f4538fe9d8827d9)"
}
],
"id": "CVE-2026-63853",
"lastModified": "2026-07-27T17:44:23.777",
"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": "2026-07-19T15:16:52.113",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/1286b6872de0aee1feeeaa6dbac86369806de9a5"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/51f694221047c84fa185be98210eb2c354ffb8c6"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/6bdd2ed6458d35c368fbe9550a4d7f342abd3a92"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Awaiting Analysis"
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-08-21T16:48:20+00:00",
"cve": "CVE-2026-63853",
"id": "CVE-2026-63853",
"initial_release_date": "2026-07-19T00:00:00+00:00",
"product_status:known_affected": "246",
"product_status:known_not_affected": "28",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: drm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63853.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-09-18T00:47:27Z",
"cve": "CVE-2026-63853",
"id": "CVE-2026-63853",
"initial_release_date": "2026-07-24T02:13:35Z",
"product_status:first_fixed": "2",
"product_status:known_affected": "482",
"product_status:known_not_affected": "239",
"product_status:recommended": "250",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-63853",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-63853.json",
"version": "9"
}
}
}
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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.
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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.
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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.
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