SEPTEMBER 19, 2026
Live Feed
Back to database
Case File

CVE-2026-55191

HIGH · CVSS 8.7 EPSS 0.60% Public Exploit

Source: NVD + CISA KEV + EPSS · Published 2026-08-19 · Last synced 2026-09-18

CyberRota Analysis

AI-Generated

FreeRDP clients prior to version 3.27.0 are vulnerable to a heap corruption issue when negotiating RDPGFX AVC444 with an H.264 decoder backend, allowing a malicious RDP server to exploit the buffer allocation process. This vulnerability can lead to client crashes and potentially enable remote code execution due to attacker-controlled memory manipulation. Organizations using FreeRDP should prioritize updating to version 3.27.0 or later to mitigate this high-severity risk.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
code execution

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-55191
Severity
HIGH
CVSS
8.7
EPSS
0.60%

Original NVD Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients that negotiate RDPGFX AVC444 with an H.264 decoder backend calculate the intermediate YUV444 allocation size in libfreerdp/codec/h264.c with 32-bit multiplication in avc444_ensure_buffer. A malicious RDP server can supply surface dimensions for which piDstStride multiplied by padDstHeight wraps to a small nonzero value, causing winpr_aligned_recalloc to allocate an undersized buffer before YUV420CombineToYUV444 writes using the actual stride and rectangle dimensions. This can cause a client crash and may permit code execution through attacker-influenced heap corruption. This issue is fixed in version 3.27.0.