CVE-2026-93067
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: drm/bridge: tc358767: clamp the reported AUX read size to the request tc_aux_transfer() clamps an AUX read to the payload limit: size_t size = min_t(size_t, DP_AUX_MAX_PAYLOAD_BYTES - 1, msg->size); After the transfer it replaces size with the byte count the controller reports in AUX_BYTES: if (size) size = FIELD_GET(AUX_BYTES, auxstatus); AUX_BYTES is GENMASK(15, 8), so it can be up to 255. Nothing clamps it back to the request. tc_aux_read_data() reads that many bytes into the 16-byte auxrdata stack buffer, then copies them into the caller buffer. A reported count of 255 makes the read run to 256 bytes and overruns both. The controller should never report more than it was asked to transfer, so this is defense in depth rather than a live hole. The reported count is only lightly trusted, and the check is cheap. Clamp it back to the request, the same way ti-sn65dsi86 does in commit aca58eac52b8 ("drm/bridge: ti-sn65dsi86: Never store more than msg->size bytes in AUX xfer").
Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:18:00.500000
Last modified
2026-10-19 10:16:56.600000
View original CVE JSON
{
"id": "CVE-2026-93067",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-17T17:18:00.500",
"lastModified": "2026-10-19T10:16:56.600",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/bridge: tc358767: clamp the reported AUX read size to the request\n\ntc_aux_transfer() clamps an AUX read to the payload limit:\n\n\tsize_t size = min_t(size_t, DP_AUX_MAX_PAYLOAD_BYTES - 1, msg->size);\n\nAfter the transfer it replaces size with the byte count the controller\nreports in AUX_BYTES:\n\n\tif (size)\n\t\tsize = FIELD_GET(AUX_BYTES, auxstatus);\n\nAUX_BYTES is GENMASK(15, 8), so it can be up to 255. Nothing clamps it\nback to the request. tc_aux_read_data() reads that many bytes into the\n16-byte auxrdata stack buffer, then copies them into the caller buffer. A\nreported count of 255 makes the read run to 256 bytes and overruns both.\n\nThe controller should never report more than it was asked to transfer, so\nthis is defense in depth rather than a live hole. The reported count is\nonly lightly trusted, and the check is cheap. Clamp it back to the request,\nthe same way ti-sn65dsi86 does in commit aca58eac52b8 (\"drm/bridge:\nti-sn65dsi86: Never store more than msg->size bytes in AUX xfer\")."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/gpu/drm/bridge/tc358767.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
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"versionType": "git",
"status": "affected"
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"defaultStatus": "affected",
"programFiles": [
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],
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{
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},
{
"version": "0",
"lessThan": "5.4",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.270",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.221",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.188",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.157",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
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},
{
"version": "6.12.110",
"lessThanOrEqual": "6.12.*",
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},
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},
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},
{
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"versionType": "original_commit_for_fix",
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}
]
}
]
}
],
"metrics": {},
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