CVE-2026-40033

FreeRDP before 3.26.0 contains a heap-buffer-overflow vulnerability in gdi_CacheToSurface that allows remote attackers to write out-of-bounds heap memory. The vulnerability occurs because rectangle validation clamps coordinates to UINT16_MAX but performs copy operations using unclamped cache entry dimensions, enabling malicious RDP servers to trigger large out-of-bounds writes and potentially achieve remote code execution or client crash.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

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/d7508ebcd82842a691ae4941e5104d14240a89ae
https://github.com/FreeRDP/FreeRDP/pull/12713
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff	Exploit Mitigation Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-heap-buffer-overflow-in-gdi-cachetosurface-via-rectangle-validation-bypass	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:36203
https://access.redhat.com/errata/RHSA-2026:46393
https://access.redhat.com/security/cve/CVE-2026-40033
https://bugzilla.redhat.com/show_bug.cgi?id=2481473
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff	Exploit Mitigation Vendor Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40033.json

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-05-26 15:16

Updated : 2026-07-27 13:17

NVD link : CVE-2026-40033

Mitre link : CVE-2026-40033

CVE.ORG link : CVE-2026-40033

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-122

Heap-based Buffer Overflow

CWE-787

Out-of-bounds Write

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