CVE-2026-64524 (GCVE-0-2026-64524)
Vulnerability from cvelistv5 – Published: 2026-07-25 09:20 – Updated: 2026-08-05 12:42
VLAI
EPSS
VEX
Title
drm/hyperv: validate resolution_count and fix WIN8 fallback
Summary
In the Linux kernel, the following vulnerability has been resolved:
drm/hyperv: validate resolution_count and fix WIN8 fallback
A SYNTHVID_RESOLUTION_RESPONSE with resolution_count > 64 walks past
the supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT] array in the
parse loop. Bound resolution_count against the array size, folded
into the existing zero-check.
When the WIN10 resolution probe fails, the caller in
hyperv_connect_vsp() left hv->screen_*_max / preferred_* unpopulated,
which sets mode_config.max_width / max_height to 0 and makes
drm_internal_framebuffer_create() reject every userspace framebuffer
with -EINVAL. The pre-WIN10 branch had the same gap for
preferred_width / preferred_height. Use a single post-probe fallback
guarded by screen_width_max == 0 so both paths converge on the WIN8
defaults.
Severity
7.7 (High)
Assigner
References
7 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
76c56a5affeba1e163b66b9d8cc192e6154466f0 , < 96f7de3172d4aa878b7f87173b2b3507c350fcd6
(git)
Affected: 76c56a5affeba1e163b66b9d8cc192e6154466f0 , < bc573752f3dac0d1ab8df7078c1851bc76717653 (git) Affected: 76c56a5affeba1e163b66b9d8cc192e6154466f0 , < 1fb565b77b8f44afabb02de6310065f109d89e94 (git) Affected: 76c56a5affeba1e163b66b9d8cc192e6154466f0 , < a321c908f2eeea01539668eb270d074d9b88e490 (git) Affected: 76c56a5affeba1e163b66b9d8cc192e6154466f0 , < 9c698b2c43c2667c34f5336bf46ad5786216ac2a (git) Affected: 76c56a5affeba1e163b66b9d8cc192e6154466f0 , < 8a114b25b5521eae451b13bce98ae978624962e5 (git) Affected: 76c56a5affeba1e163b66b9d8cc192e6154466f0 , < 13d33b9ef67066c77c84273fac5a1d3fde3533d1 (git) |
guessed | |
| Linux | Linux |
Affected:
5.14
Unaffected: 0 , < 5.14 (semver) Unaffected: 5.15.210 , ≤ 5.15.* (semver) Unaffected: 6.1.176 , ≤ 6.1.* (semver) Unaffected: 6.6.143 , ≤ 6.6.* (semver) Unaffected: 6.12.93 , ≤ 6.12.* (semver) Unaffected: 6.18.35 , ≤ 6.18.* (semver) Unaffected: 7.0.12 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/hyperv/hyperv_drm_proto.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "96f7de3172d4aa878b7f87173b2b3507c350fcd6",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "bc573752f3dac0d1ab8df7078c1851bc76717653",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "1fb565b77b8f44afabb02de6310065f109d89e94",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "a321c908f2eeea01539668eb270d074d9b88e490",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "9c698b2c43c2667c34f5336bf46ad5786216ac2a",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "8a114b25b5521eae451b13bce98ae978624962e5",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "13d33b9ef67066c77c84273fac5a1d3fde3533d1",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/hyperv/hyperv_drm_proto.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.14"
},
{
"lessThan": "5.14",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.93",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.35",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.12",
"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": "5.15.210",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.176",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.143",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.93",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.35",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.0.12",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1",
"versionStartIncluding": "5.14",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/hyperv: validate resolution_count and fix WIN8 fallback\n\nA SYNTHVID_RESOLUTION_RESPONSE with resolution_count \u003e 64 walks past\nthe supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT] array in the\nparse loop. Bound resolution_count against the array size, folded\ninto the existing zero-check.\n\nWhen the WIN10 resolution probe fails, the caller in\nhyperv_connect_vsp() left hv-\u003escreen_*_max / preferred_* unpopulated,\nwhich sets mode_config.max_width / max_height to 0 and makes\ndrm_internal_framebuffer_create() reject every userspace framebuffer\nwith -EINVAL. The pre-WIN10 branch had the same gap for\npreferred_width / preferred_height. Use a single post-probe fallback\nguarded by screen_width_max == 0 so both paths converge on the WIN8\ndefaults."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.7,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The malicious resolution response must originate from the local Hyper-V synthetic-video backend over VMBus; it is not reachable through a network protocol or guest userspace ioctl.\nAC:L - The backend can deterministically trigger the flaw by returning a resolution_count from 65 through 255 during the normal WIN10+ probe or resume exchange, without a race or unpredictable condition.\nPR:N - The guest accepts the VMBus response without authentication, capability checks, or guest credentials; a malicious or compromised backend requires no privileges within the vulnerable guest.\nUI:N - The response is processed automatically during device probing or resume, without any victim action.\nS:U - The vulnerable parser and the affected DRM and kernel resources are within the same guest-kernel security authority; this does not produce a guest-to-host escape.\nC:H - A count of 255 causes 191 additional four-byte entries to be read beyond the declared array, substantially exceeding a small bounded disclosure and allowing out-of-bounds kernel data to influence observable display state.\nI:N - The invalid accesses are reads, and their results are written only to the intended resolution fields; no out-of-bounds write, use-after-free, or control-flow corruption was found.\nA:H - Bounds-instrumented hardened kernels can oops when index 64 is reached, while a failed or malformed resolution probe can leave zero maximum dimensions and make every userspace framebuffer creation fail."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-05T12:42:37.752Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/96f7de3172d4aa878b7f87173b2b3507c350fcd6"
},
{
"url": "https://git.kernel.org/stable/c/bc573752f3dac0d1ab8df7078c1851bc76717653"
},
{
"url": "https://git.kernel.org/stable/c/1fb565b77b8f44afabb02de6310065f109d89e94"
},
{
"url": "https://git.kernel.org/stable/c/a321c908f2eeea01539668eb270d074d9b88e490"
},
{
"url": "https://git.kernel.org/stable/c/9c698b2c43c2667c34f5336bf46ad5786216ac2a"
},
{
"url": "https://git.kernel.org/stable/c/8a114b25b5521eae451b13bce98ae978624962e5"
},
{
"url": "https://git.kernel.org/stable/c/13d33b9ef67066c77c84273fac5a1d3fde3533d1"
}
],
"title": "drm/hyperv: validate resolution_count and fix WIN8 fallback",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-64524",
"datePublished": "2026-07-25T09:20:48.193Z",
"dateReserved": "2026-07-19T15:36:31.794Z",
"dateUpdated": "2026-08-05T12:42:37.752Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-64524",
"date": "2026-10-02",
"epss": "0.00142",
"percentile": "0.02927"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/hyperv/hyperv_drm_proto.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "96f7de3172d4aa878b7f87173b2b3507c350fcd6",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "bc573752f3dac0d1ab8df7078c1851bc76717653",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "1fb565b77b8f44afabb02de6310065f109d89e94",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "a321c908f2eeea01539668eb270d074d9b88e490",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "9c698b2c43c2667c34f5336bf46ad5786216ac2a",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "8a114b25b5521eae451b13bce98ae978624962e5",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
},
{
"lessThan": "13d33b9ef67066c77c84273fac5a1d3fde3533d1",
"status": "affected",
"version": "76c56a5affeba1e163b66b9d8cc192e6154466f0",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/gpu/drm/hyperv/hyperv_drm_proto.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.14"
},
{
"lessThan": "5.14",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.93",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.35",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.12",
"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/hyperv: validate resolution_count and fix WIN8 fallback\n\nA SYNTHVID_RESOLUTION_RESPONSE with resolution_count \u003e 64 walks past\nthe supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT] array in the\nparse loop. Bound resolution_count against the array size, folded\ninto the existing zero-check.\n\nWhen the WIN10 resolution probe fails, the caller in\nhyperv_connect_vsp() left hv-\u003escreen_*_max / preferred_* unpopulated,\nwhich sets mode_config.max_width / max_height to 0 and makes\ndrm_internal_framebuffer_create() reject every userspace framebuffer\nwith -EINVAL. The pre-WIN10 branch had the same gap for\npreferred_width / preferred_height. Use a single post-probe fallback\nguarded by screen_width_max == 0 so both paths converge on the WIN8\ndefaults."
}
],
"id": "CVE-2026-64524",
"lastModified": "2026-07-27T05:16:56.447",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.7,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 2.5,
"impactScore": 5.2,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
}
]
},
"published": "2026-07-25T10:17:38.713",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/13d33b9ef67066c77c84273fac5a1d3fde3533d1"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/1fb565b77b8f44afabb02de6310065f109d89e94"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/8a114b25b5521eae451b13bce98ae978624962e5"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/96f7de3172d4aa878b7f87173b2b3507c350fcd6"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/9c698b2c43c2667c34f5336bf46ad5786216ac2a"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/a321c908f2eeea01539668eb270d074d9b88e490"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/bc573752f3dac0d1ab8df7078c1851bc76717653"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Received"
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-08-05T14:15:27+00:00",
"cve": "CVE-2026-64524",
"id": "CVE-2026-64524",
"initial_release_date": "2026-07-25T00:00:00+00:00",
"product_status:known_affected": "184",
"product_status:known_not_affected": "91",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: drm/hyperv: validate resolution_count and fix WIN8 fallback",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64524.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-09-22T16:51:51Z",
"cve": "CVE-2026-64524",
"id": "CVE-2026-64524",
"initial_release_date": "2026-07-25T15:57:46Z",
"product_status:first_fixed": "91",
"product_status:known_affected": "440",
"product_status:known_not_affected": "293",
"product_status:recommended": "107",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-64524",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64524.json",
"version": "11"
}
}
}
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…
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…