CVE-2026-55191highCWE-122CWE-190

CVE-2026-55191: high-severity vulnerability in FreeRDP

FreeRDP: Heap-buffer-overflow write in AVC444 YUV buffer allocation

Published

Follow this CVE+ Monitor FreeRDP+ Monitor freerdp2

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.7epss 0.6%
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.
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
Affected products
FreeRDP · FreeRDP
Related CVEs — FreeRDP

In the same product, most dangerous first.

CVE-2026-45700HIGHHeap-buffer-overflow write in planar bitmap decoderEPSS 6.1%CVE-2026-44420HIGHFreeRDP cliprdr server heap-buffer-overflow via undersized capabilitySetLength in CB_CLIP_CAPSEPSS 4.6%CVE-2024-32459CRITICALFreeRDP Out-Of-Bounds Read in ncrush_decompressEPSS 3.7%CVE-2022-24882CRITICALServer side NTLM does not properly check parameters in FreeRDPEPSS 2.8%CVE-2022-24883HIGHFreeRDP Server authentication might allow invalid credentials to passEPSS 2.3%CVE-2020-11019MEDIUMOut of bound read in update_recv in FreeRDPEPSS 2.3%