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CVE-2026-67303 (GCVE-0-2026-67303)

Vulnerability from cvelistv5 – Published: 2026-08-01 12:22 – Updated: 2026-08-03 19:45
VLAI
Title
FreeRDP before 3.29.0 Denial of Service via serial DeviceControl
Summary
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).
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 19:44 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: 0 , < 3.29.0 (semver)
Unaffected: 3.29.0 (semver)
    cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-15 00:00
Credits
1121984919
Show details on NVD website
To clipboard 

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