CVE-2026-55191

{"id": "CVE-2026-55191", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-55191", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-08-19T18:15:35.235601Z"}}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.7, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "FreeRDP", "product": "FreeRDP", "versions": [{"status": "affected", "version": "< 3.27.0"}]}]}], "published": "2026-08-19T18:16:44.427", "references": [{"url": "https://github.com/FreeRDP/FreeRDP/commit/97f40b9e766af375f4e41ac6a3f4397d708d249c", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/pull/12873", "tags": ["Issue Tracking", "Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vx73-w5q6-7jqr", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vx73-w5q6-7jqr", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-122"}, {"lang": "en", "value": "CWE-190"}]}], "descriptions": [{"lang": "en", "value": "FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients that negotiate RDPGFX AVC444 with an H.264 decoder backend calculate the intermediate YUV444 allocation size in libfreerdp/codec/h264.c with 32-bit multiplication in avc444_ensure_buffer. A malicious RDP server can supply surface dimensions for which piDstStride multiplied by padDstHeight wraps to a small nonzero value, causing winpr_aligned_recalloc to allocate an undersized buffer before YUV420CombineToYUV444 writes using the actual stride and rectangle dimensions. This can cause a client crash and may permit code execution through attacker-influenced heap corruption. This issue is fixed in version 3.27.0."}, {"lang": "es", "value": "FreeRDP es una implementaci\u00f3n gratuita del Protocolo de Escritorio Remoto. Antes de la versi\u00f3n 3.27.0, los clientes FreeRDP que negocian RDPGFX AVC444 con un backend de decodificador H.264 calculan el tama\u00f1o de asignaci\u00f3n YUV444 intermedio en libfreerdp/codec/h264.c con multiplicaci\u00f3n de 32 bits en avc444_ensure_buffer. Un servidor RDP malicioso puede proporcionar dimensiones de superficie para las cuales piDstStride multiplicado por padDstHeight se desborda a un valor peque\u00f1o distinto de cero, lo que hace que winpr_aligned_recalloc asigne un b\u00fafer de tama\u00f1o insuficiente antes de que YUV420CombineToYUV444 escriba utilizando las dimensiones reales de paso y rect\u00e1ngulo. Esto puede causar un fallo del cliente y puede permitir la ejecuci\u00f3n de c\u00f3digo a trav\u00e9s de la corrupci\u00f3n de la pila influenciada por el atacante. Este problema est\u00e1 solucionado en la versi\u00f3n 3.27.0."}], "lastModified": "2026-10-26T11:10:00.157", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F9603C86-160B-40E9-BA5D-813AA03B1A44", "versionEndExcluding": "3.27.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}