Name: CVE-2026-55193: Heap-based Buffer Overflow
Creator: Rapid7
Published: 2026-08-19T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-55193, CWE-122, CVSS 8.8, EPSS 0.00479

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients using TS Gateway accept a server-controlled max_xmit_frag value in libfreerdp/core/gateway/rpc_bind.c without bounding it to the 4088-byte ReceiveFragment allocation. A malicious gateway can advertise 65535 and then send a response fragment of the same length, causing rpc_channel_read in libfreerdp/core/gateway/rpc.c to write up to 65535 bytes into the smaller ReceiveFragment buffer. This can crash the client and may permit code execution through attacker-controlled heap corruption. This issue is fixed in version 3.27.0.

CVSS Details

CVSS 4.0 Base Score: 8.7 (HIGH)
CVSS 4.0 Vector: (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)
CVSS 3.1 Base Score: 8.8
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alma_linux	—	Upgrade libwinpr-develUpgrade libwinprUpgrade freerdpUpgrade freerdp-develUpgrade freerdp-libs	Oct 11, 2026	Sep 10, 2026
Alpine Linux	—	Upgrade freerdp	Aug 20, 2026	Aug 19, 2026
Amazon Linux Ami 2	—	Upgrade freerdp-debuginfoUpgrade libwinpr-develUpgrade freerdpUpgrade libwinprUpgrade freerdp-develUpgrade freerdp-libs	Aug 5, 2026	Aug 5, 2026
Oracle_linux	—	Upgrade freerdp-libsUpgrade libwinprUpgrade freerdp-develUpgrade freerdp-serverUpgrade freerdpUpgrade libwinpr-devel	Oct 22, 2026	Aug 19, 2026
Redhat_linux	—	Upgrade freerdp-libsUpgrade freerdp-develUpgrade freerdp-debuginfoUpgrade libwinpr-develUpgrade freerdp-serverUpgrade freerdpUpgrade freerdp-debugsourceNo solution existsUpgrade freerdp-libs-debuginfoUpgrade libwinprUpgrade libwinpr-debuginfoUpgrade freerdp-server-debuginfo	Aug 26, 2026	Aug 19, 2026
Rocky_linux	—	Upgrade freerdp-develUpgrade freerdp-libs-debuginfoUpgrade libwinprUpgrade freerdp-server-debuginfoUpgrade freerdpUpgrade freerdp-debugsourceUpgrade libwinpr-develUpgrade freerdp-libsUpgrade libwinpr-debuginfoUpgrade freerdp-debuginfoUpgrade freerdp-server	Sep 15, 2026	Sep 11, 2026
Ubuntu	—	Upgrade freerdp3-x11Upgrade freerdp-x11Upgrade libfreerdp3-3	Jul 21, 2026	Jul 20, 2026

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CVSS Details

Covered by Rapid7

Prioritize with Active Threat Intelligence