Description
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).
Affected products
freerdp: freerdp
References4
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-pfxq-3qmw-8… MitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/commit/1cc783d4c78bd2f66d3a8582dfe70… Patch
- github.com/FreeRDP/FreeRDP/commit/5370fb26fbf034ecd11d3026b6ad6… Patch
- www.vulncheck.com/advisories/freerdp-before-denial-of-service-v… PatchThird Party Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L - CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 37 · as of 13 November 2026
- CWE
- CWE-617
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