CVE-2026-67298

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/46848765f2a1134f8652f8760eefb5e85d64a9b8
https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmvw-52ph-q5pv
https://www.vulncheck.com/advisories/freerdp-heap-buffer-overflow-via-rail-orderlength-underflow
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-5wr6-8m8j-3h7f

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-01 13:16

Updated : 2026-08-31 20:25

NVD link : CVE-2026-67298

Mitre link : CVE-2026-67298

CVE.ORG link : CVE-2026-67298

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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