Integer Underflow Affecting freerdp3 package, versions <3.29.0+dfsg-1


Severity

Recommended
0.0
high
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
0.38% (31st percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-DEBIAN14-FREERDP3-18505511
  • published2 Aug 2026
  • disclosed1 Aug 2026

Introduced: 1 Aug 2026

NewCVE-2026-67298  (opens in a new tab)
CWE-191  (opens in a new tab)

How to fix?

Upgrade Debian:14 freerdp3 to version 3.29.0+dfsg-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream freerdp3 package and not the freerdp3 package as distributed by Debian. See How to fix? for Debian:14 relevant fixed versions and status.

FreeRDP versions 3.28.0 and earlier contain a heap buffer overflow in the server-side RAIL channel handler (rail_server_handle_messages() in channels/rail/server/rail_main.c). When processing a RAIL PDU header, the code subtracts RAIL_PDU_HEADER_LENGTH from the peer-controlled orderLength field without first verifying orderLength is at least the header length. For orderLength values 0..3 this causes an unsigned integer underflow to a very large size, which bypasses the Stream_EnsureRemainingCapacity() capacity check (due to pointer arithmetic wraparound) and is then passed to WTSVirtualChannelRead(), resulting in an out-of-bounds heap write. A malicious or compromised RDP client can exploit this to corrupt the heap and crash the server. Fixed in FreeRDP 3.29.0.

CVSS Base Scores

version 3.1