CVE-2026-55827

HIGH

FreeRDP: Heap out-of-bounds write in RemoteFX (RFX) Cache Bitmap V3 decode

Title source: cna
STIX 2.1

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.1, FreeRDP clients launched with the non-default /cache:codec:rfx option pass desktop stride and height to RemoteFX decoding for Cache Bitmap V3 data while allocating bitmap->data only for the smaller DstWidth and DstHeight in gdi_Bitmap_Decompress, allowing a malicious RDP server to trigger a heap out-of-bounds write with attacker-controlled offset and content. This issue is fixed in version 3.27.1.

References (4)

Core 4

Scores

CVSS v3 7.5
EPSS 0.0045
EPSS Percentile 36.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact total

Details

CWE
CWE-131 CWE-787
Status published
Products (2)
freerdp/freerdp < 3.27.1
FreeRDP/FreeRDP < 3.27.1
Published Jul 10, 2026
Tracked Since Jul 11, 2026