High 8.8Published May 26, 2026

CVE-2026-40033FreeRDP - Heap-buffer-overflow in gdi_CacheToSurface via rectangle validation bypass

Updated under an hour ago (Oct 26, 2026, 9:40 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for FreeRDP

Exploited in the last 30 days

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: 8.8 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-122, CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Modified
Record last updated: Jul 27, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

FreeRDP FreeRDP freerdp:freerdp (from the name)	before 3.26.0; 3.26.0 not affected	CNA record
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux	from 2:3.10.3-12.el10_2.6 not affected	CISA ADP
freerdp freerdp freerdp:freerdp	before 3.26.0	NVD

References

References

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff	vendor-advisory, exploit, mitigation
https://github.com/FreeRDP/FreeRDP/pull/12713	issue-tracking
https://github.com/FreeRDP/FreeRDP/commit/d7508ebcd82842a691ae4941e5104d14240a89ae	patch
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://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40033.json

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.