CVE-2026-55827

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.1, FreeRDP clients launched with the non-default /cache:codec:rfx option pass desktop stride and height to RemoteFX decoding for Cache Bitmap V3 data while allocating bitmap->data only for the smaller DstWidth and DstHeight in gdi_Bitmap_Decompress, allowing a malicious RDP server to trigger a heap out-of-bounds write with attacker-controlled offset and content. This issue is fixed in version 3.27.1.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/e58adf922ea4c0d5495e59a1fe488d70092e0e3e	Patch
https://github.com/FreeRDP/FreeRDP/pull/12899	Patch
https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.1	Release Notes
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-c495-h83v-3prp	Exploit Mitigation Vendor Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-c495-h83v-3prp	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-10 20:16

Updated : 2026-07-15 05:17

NVD link : CVE-2026-55827

Mitre link : CVE-2026-55827

CVE.ORG link : CVE-2026-55827

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-131

Incorrect Calculation of Buffer Size

CWE-787

Out-of-bounds Write

{"id": "CVE-2026-55827", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-55827", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-07-14T00:00:00+00:00"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.6}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "FreeRDP", "product": "FreeRDP", "versions": [{"status": "affected", "version": "< 3.27.1"}]}]}], "published": "2026-07-10T20:16:48.060", "references": [{"url": "https://github.com/FreeRDP/FreeRDP/commit/e58adf922ea4c0d5495e59a1fe488d70092e0e3e", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/pull/12899", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.1", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-c495-h83v-3prp", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-c495-h83v-3prp", "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-131"}, {"lang": "en", "value": "CWE-787"}]}], "descriptions": [{"lang": "en", "value": "FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.1, FreeRDP clients launched with the non-default /cache:codec:rfx option pass desktop stride and height to RemoteFX decoding for Cache Bitmap V3 data while allocating bitmap->data only for the smaller DstWidth and DstHeight in gdi_Bitmap_Decompress, allowing a malicious RDP server to trigger a heap out-of-bounds write with attacker-controlled offset and content. This issue is fixed in version 3.27.1."}], "lastModified": "2026-07-15T05:17:15.187", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2A25C5E0-4DFB-4BAA-8C4B-6B808F0F8984", "versionEndExcluding": "3.27.1"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}