CVE-2026-67303

FreeRDP before 3.29.0 contains a reachable assertion (WINPR_ASSERT(OutputBufferLength == BytesReturned)) in serial_process_irp_device_control() in channels/serial/client/serial_main.c. When serial device redirection is enabled and a server-controlled IRP_MJ_DEVICE_CONTROL request specifies an unsupported IOCTL with a non-zero OutputBufferLength, CommDeviceIoControl() can fail with BytesReturned = 0, causing the mismatch to trigger the assertion and abort the client process (denial of service).

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/1cc783d4c78bd2f66d3a8582dfe70a663d141444
https://github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad639b5fff493f
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-pfxq-3qmw-8vjx
https://www.vulncheck.com/advisories/freerdp-before-denial-of-service-via-serial-devicecontrol

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-01 13:16

Updated : 2026-08-31 20:25

NVD link : CVE-2026-67303

Mitre link : CVE-2026-67303

CVE.ORG link : CVE-2026-67303

JSON object : View

Products Affected

No product.

CWE

CWE-617

Reachable Assertion

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