CVE-2026-40033

highpriority · track · 0EPSS 0.014 · 72 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
1.36% (72nd) EPSS
CVSS 8.8 · high
Is it mine?
15 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.3–8.8

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · disclosure@vulncheck.comexploitability 2.8 · impact 5.9
v3.18.8highAV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondaryexploitability 2.8 · impact 5.9
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · OSV
v4.08.6highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU
v4.08.7highCVSS: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:Xsecondary · disclosure@vulncheck.com
v4.06.3mediumCVSS: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:U/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:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-122USCWE-122USCWE-122USCWE-787US
04

affected products (15)

Products and version ranges known to be affected.

05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-1470FreeRDP: Mehrere SchwachstellenDeutsch2026-05-11csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in FreeRDP ausnutzen, um beliebigen Programmcode auszuführen, einen Denial-of-Service-Zustand zu verursachen oder nicht näher spezifizierte Angriffe durchzuführen.

  • CVE-2026-44421FreeRDP RDPGFX CacheToSurface heap-buffer-overflow via clamped-rectangle validation bypass2026-05-29vendor · osvUS

    FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.

06

also known as (6)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bduosvcert_bundnvdNVDCVE.orgMITRE
published 2026-05-26modified 2026-07-27
08

references (17)

External citations — patches, advisories, analysis.

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