Skip to main content
HIGH

CVE-2026-40033

CVSS v3

8.8

HIGH

EPSS Score

1.1 %

exploit probability, as of 2026-10-19

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Get an alert for each new CVE published for freerdp.

Set up CVE WatchFree account · no credit card

Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • freerdpAlmaLinux:10all versions · fixed in 2:3.10.3-12.el10_2.6and 5 other packages

Vendor advisories

  • CVE-2026-40033 Red Hat Product Security130 products fixed · 11 known affected

    freerdp: FreeRDP: Remote code execution via heap-buffer-overflow in gdi_CacheToSurface

    freerdp as a component of Red Hat Enterprise Linux 6 · freerdp-devel as a component of Red Hat Enterprise Linux 6 · freerdp-libs as a component of Red Hat Enterprise Linux 6

  • RHSA-2026:46393 Red Hat Product Security65 products fixed

    Red Hat Security Advisory: freerdp security update

  • RHSA-2026:36203 Red Hat Product Security65 products fixed

    Red Hat Security Advisory: freerdp security update

Full record on NVD

Description

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.

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Published
2026-05-26
Last Modified
2026-07-27

Frequently asked questions

What is 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.

Is CVE-2026-40033 actively exploited?

Active exploitation of CVE-2026-40033 has not been confirmed. Its EPSS score was 1.1% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-40033?

CVE-2026-40033 has a CVSS v3 base score of 8.8 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Running freerdp? Hear about its next vulnerability

CVE Watch matches each new CVE to the vendors and products you list (vendor and product, not the version) and puts it in your alerts with its KEV and EPSS status.

Get alerts for this productCISA KEV additions, October 2026Search CVEs

Already have an account? Open CVE WatchNo credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database