Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
FreeRDP - Heap-buffer-overflow in gdi_CacheToSurface via rectangle validation bypass
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV
N L N N P H H H 8.7 .0104 61.2 —
AFFECTED
Product Versions Fixed
FreeRDP unspecified 3.26.0
TIMELINE
Apr 8 Reserved by VulnCheck
May 26 EXPLOIT PUBLISHED — CVE-2026-40033 (FreeRDP). Public exploit reference added.
May 26 Published (CNA: VulnCheck)
Jul 27 EXPLOIT PUBLISHED — CVE-2026-40033 (FreeRDP). Public exploit reference added.
Jul 27 RESCORED — CVE-2026-40033 (FreeRDP). CVSS 8.6 → 8.7 (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.
Lifecycle
Complete event history — 5 events, chronological
| Date | Event | Detail |
|---|
| April 8, 2026 | Reserved | Reserved by VulnCheck |
| May 26, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-40033 (FreeRDP). Public exploit reference added. |
| May 26, 2026 | Published | Published (CNA: VulnCheck) |
| July 27, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-40033 (FreeRDP). Public exploit reference added. |
| July 27, 2026 | RESCORED | RESCORED — CVE-2026-40033 (FreeRDP). CVSS 8.6 → 8.7 (NVD). |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| FreeRDP | FreeRDP | — | — | 3.26.0 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-40033 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.