Dashboard / CVE-2026-55191

CVE-2026-55191

HIGH
MEDIUM Priority: 0.05 BB Relevance: 68/100
Published: 2026-08-19 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Passive
S: X
AT: None
VC: High
VI: High
VA: High

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.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
freerdp freerdp < 3.27.0

References & Advisories (4)

Bug Bounty Relevance

68 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

8.7 / 10.0 v4.0
CVSS: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:X

EPSS — Exploitation Probability

0.62%
Raw Score 0.006190
Percentile 49.6%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00619
2026-10-28
0.00619

Intelligence Sources

nvd ref →

External Links