CVE-2026-67300
Full vulnerability record from the local CVENow database.
Description
FreeRDP before 3.29.0 contains client-side heap use-after-free vulnerabilities in the async update message proxy for RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER when AsyncUpdate is enabled. When a malicious or compromised RDP server sends crafted update orders, the message proxy shallow-copies structures containing nested parser-owned pointers (e.g., titleInfo.string, windowRects, visibilityRects, icon buffers). The parser frees those nested buffers after the callback returns, so the queued async message later dispatches stale pointers, potentially causing memory corruption or a client crash.
Severity
HIGH
CVSS score
8.7
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-08-01 13:16:59.393000
Last modified
2026-11-03 21:38:47.550000
View original CVE JSON
{
"id": "CVE-2026-67300",
"sourceIdentifier": "[email protected]",
"published": "2026-08-01T13:16:59.393",
"lastModified": "2026-11-03T21:38:47.550",
"vulnStatus": "Analyzed",
"cveTags": [],
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"value": "FreeRDP before 3.29.0 contains client-side heap use-after-free vulnerabilities in the async update message proxy for RAIL WINDOW_STATE_ORDER and NOTIFY_ICON_STATE_ORDER when AsyncUpdate is enabled. When a malicious or compromised RDP server sends crafted update orders, the message proxy shallow-copies structures containing nested parser-owned pointers (e.g., titleInfo.string, windowRects, visibilityRects, icon buffers). The parser frees those nested buffers after the callback returns, so the queued async message later dispatches stale pointers, potentially causing memory corruption or a client crash."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "FreeRDP",
"product": "FreeRDP",
"defaultStatus": "unaffected",
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{
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},
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}
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}
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],
"metrics": {
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"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
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"weaknesses": [
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"type": "Secondary",
"description": [
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"configurations": [
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}