CVE-2026-121951 FreeRDP 3.0.0 before 3.32.2 Denial of Service via Slow-Path Input Event

What is CVE-2026-121951?

CVE-2026-121951 is a high-severity vulnerability in FreeRDP, published on 4 Nov 2026.

Official description

FreeRDP 3.0.0 before 3.32.2 server-side RDP peer input parsing skips the six-byte body of a slow-path input event with an unknown message type without checking it lies within the packet's declared length, causing a WinPR stream assertion failure. A remote RDP client with an active session can send a truncated unknown input event to abort assertion-enabled server processes, causing denial of service.

Weakness: CWE-617

Which versions are affected by CVE-2026-121951?

It affects 1 product.

Products include FreeRDP.

How do I fix CVE-2026-121951?

Upgrade to a fixed version.

Is CVE-2026-121951 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-121951 exists.

Other vulnerabilities in FreeRDP

• CVE-2024-32658 FreeRDP ExtractRunLengthRegular* out of bound read Critical 9.8
• CVE-2024-32659 freerdp_image_copy out of bound read Critical 9.8
• CVE-2024-32039 FreeRDP Integer overflow & OutOfBound Write in clear_decompress_residual_data Critical 9.8
• CVE-2024-32041 FreeRDP OutOfBound Read in zgfx_decompress_segment Critical 9.8
• CVE-2024-32458 FreeRDP Out-Of-Bounds Read in planar_skip_plane_rle Critical 9.8

All FreeRDP vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2026-121951, GHSA-4qq4-qwxq-49m8, GHSA-wcwc-8x6v-rgcq, UBUNTU-CVE-2026-121951.