TI-2026-40174 Aliases CVE-2026-55648

FreeRDP: Integer Overflow in `freerdp_image_copy_from_icon_data` Bypasses Bounds Check

LOW 28CWE-190Published 2026-08-19 · Updated 2026-08-21

Key facts

Attack vector: Network
Privileges required: None
User interaction: Passive
Attack complexity: Low
Attack requirements: Present
Impact type: —
Confidentiality · integrity · availability: High · None · High
Fix status: Partial Red Hat: 5 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, freerdp_image_copy_from_icon_data in libfreerdp/codec/color.c calculates nWidth multiplied by nHeight multiplied by FreeRDPGetBytesPerPixel(format) in 32-bit arithmetic. A malicious RDP server can send a RAIL TS_ICON_INFO update with dimensions such as 32768 by 32768 and 32 bits per pixel so the required-size calculation wraps, bypassing the cbBitsColor source bounds check before freerdp_image_copy_no_overlap reads attacker-controlled icon data. This affects RemoteApp clients using the vulnerable library path, while xfreerdp has a caller-side mitigation. This issue is fixed in version 3.27.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00432 37th percentileScored 2026-11-07

Fix Partial FreeRDP (FreeRDP): 3.27.0Red Hat: 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
FreeRDP	FreeRDP	before 3.27.0	3.27.0	Patch available	CNA

FreeRDP VendorFreeRDP Affected before 3.27.0 Fixed in 3.27.0 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:freerdp:freerdp::::::::	before 3.27.0	Vulnerable	FreeRDP

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:* Versions before 3.27.0 Vulnerable ·FreeRDP

Remediation

Fix · CNA FreeRDP (FreeRDP) Fixed in 3.27.0

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 10	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 6	Affected	No fix planned: Out of support scope
Red Hat Enterprise Linux 7	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 8	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 9	Affected	No fix yet: Fix deferred

Timeline

2026-10-02 Threatist record created from CVE-2026-55648

References

Patch 2

Advisory 1

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-5c5v-f78v-h2f6

Other 1

https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0

TI-2026-85092 Use-after-free in FreeRDP rdpgfx channel close handling CVSS 4.0CRITICAL 9.3
TI-2026-85091 Out-of-bounds write in FreeRDP proxy via bitmap cache v2 capability CVSS 4.0CRITICAL 9.3
TI-2026-24435 FreeRDP has a `size_t` underflow in ADPCM decoder leads to heap-buffer-overflow write CVSS 3.1CRITICAL 9.8
TI-2023-21373 Out-Of-Bounds Write in FreeRDP CVSS 3.1CRITICAL 9.8
TI-2022-08692 Server side NTLM does not properly check parameters in FreeRDP CVSS 3.1CRITICAL 9.1
TI-2023-21374 Out-Of-Bounds Read in FreeRDP CVSS 3.1CRITICAL 9.1

See all 336 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences