CVE-2026-55192
Full vulnerability record from the local CVENow database.
Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP H.264 decoder backends can return YUV planes sized from the bitstream without comparing the decoded width and height to the RDPGFX surface dimensions used to validate region rectangles. A malicious RDP server can provide an AVC420 or AVC444 bitstream whose decoded frame is smaller than the negotiated surface, causing yuv420_context_decode and the YUV-to-RGB conversion paths to read beyond the decoder-owned planes in libfreerdp/codec/h264.c and the selected H.264 backend. This can disclose client memory or crash the client. This issue is fixed in version 3.27.0.
Severity
HIGH
CVSS score
7.2
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-08-19 18:16:44.580000
Last modified
2026-10-26 11:10:00.157000
View original CVE JSON
{
"id": "CVE-2026-55192",
"sourceIdentifier": "[email protected]",
"published": "2026-08-19T18:16:44.580",
"lastModified": "2026-10-26T11:10:00.157",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP H.264 decoder backends can return YUV planes sized from the bitstream without comparing the decoded width and height to the RDPGFX surface dimensions used to validate region rectangles. A malicious RDP server can provide an AVC420 or AVC444 bitstream whose decoded frame is smaller than the negotiated surface, causing yuv420_context_decode and the YUV-to-RGB conversion paths to read beyond the decoder-owned planes in libfreerdp/codec/h264.c and the selected H.264 backend. This can disclose client memory or crash the client. This issue is fixed in version 3.27.0."
},
{
"lang": "es",
"value": "FreeRDP es una implementación gratuita del Protocolo de Escritorio Remoto. Antes de la 3.27.0, los backends del decodificador H.264 de FreeRDP pueden devolver planos YUV dimensionados a partir del flujo de bits sin comparar el ancho y alto decodificados con las dimensiones de la superficie RDPGFX utilizadas para validar rectángulos de región. Un servidor RDP malicioso puede proporcionar un flujo de bits AVC420 o AVC444 cuyo fotograma decodificado es más pequeño que la superficie negociada, lo que hace que yuv420_context_decode y las rutas de conversión de YUV a RGB lean más allá de los planos propiedad del decodificador en libfreerdp/codec/h264.c y el backend H.264 seleccionado. Esto puede divulgar memoria del cliente o bloquear el cliente. Este problema está solucionado en la versión 3.27.0."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "FreeRDP",
"product": "FreeRDP",
"versions": [
{
"version": "< 3.27.0",
"status": "affected"
}
]
}
]
}
],
"metrics": {
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"type": "Secondary",
"cvssData": {
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"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
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"vulnIntegrityImpact": "NONE",
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"subAvailabilityImpact": "NONE",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"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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"cvssMetricV31": [
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"ssvcV203": [
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"id": "CVE-2026-55192",
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{
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"role": "CISA Coordinator",
"version": "2.0.3"
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-125"
}
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"configurations": [
{
"nodes": [
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"negate": false,
"cpeMatch": [
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"references": [
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"source": "[email protected]",
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"source": "[email protected]",
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},
{
"url": "https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0",
"source": "[email protected]",
"tags": [
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},
{
"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mmf-qh4f-frm6",
"source": "[email protected]",
"tags": [
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}