CVE-2026-68445
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: drm/vc4: Prevent shader BO mappings from becoming writable vc4_gem_object_mmap() rejects a writable mapping of a validated shader BO, but leaves VM_MAYWRITE set. Userspace can map the BO read-only and then turn it writable with mprotect(). Validated shader BOs must stay read-only: the validator checks the instructions once and the GPU trusts them afterwards. A writable mapping lets userspace rewrite the code after validation, bypassing the validator. Clear VM_MAYWRITE on the read-only path so the mapping cannot be upgraded, as i915 already does for its read-only objects.
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-12 00:17:44.860000
Last modified
2026-10-30 13:19:45.717000
View original CVE JSON
{
"id": "CVE-2026-68445",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-08-12T00:17:44.860",
"lastModified": "2026-10-30T13:19:45.717",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/vc4: Prevent shader BO mappings from becoming writable\n\nvc4_gem_object_mmap() rejects a writable mapping of a validated shader\nBO, but leaves VM_MAYWRITE set. Userspace can map the BO read-only and\nthen turn it writable with mprotect().\n\nValidated shader BOs must stay read-only: the validator checks the\ninstructions once and the GPU trusts them afterwards. A writable\nmapping lets userspace rewrite the code after validation, bypassing the\nvalidator.\n\nClear VM_MAYWRITE on the read-only path so the mapping cannot be\nupgraded, as i915 already does for its read-only objects."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/gpu/drm/vc4/vc4_bo.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "463873d5701427f2964a0b4b72c45f1f14b6df87",
"lessThan": "4c98260a967e8536c69437b8da8eea3188cd6db8",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "9f0ee411fc2d76333d6087c5862ffa907cf7a175",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "019e6ad247f7fd038d2e009789f6d9bfcccb1ae7",
"versionType": "git",
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},
{
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},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"drivers/gpu/drm/vc4/vc4_bo.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "4.5",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.5",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.148",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.101",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.42",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1.6",
"lessThanOrEqual": "7.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2",
"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/019e6ad247f7fd038d2e009789f6d9bfcccb1ae7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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{
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{
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}
]
}