CVE-2026-121964 FreeRDP before 3.32.2 Heap Buffer Overflow via rpc_client_recv_fragment

What is CVE-2026-121964?

CVE-2026-121964 is a high-severity vulnerability in FreeRDP, published on 4 Nov 2026.

Official description

FreeRDP before 3.32.2 contains a heap-based buffer overflow in the RD Gateway RPC client, where rpc_client_recv_fragment writes BIND_ACK and ALTER_CONTEXT_RESP fragments into a persistent PDU stream after checking only total capacity rather than remaining capacity from the current stream position. A malicious or compromised RD Gateway can send crafted RPC fragments with manipulated alloc_hint and frag_length values to overwrite client heap memory with attacker-controlled data, causing a crash or potentially arbitrary code execution.

Weakness: CWE-122

Which versions are affected by CVE-2026-121964?

It affects 1 product.

Products include FreeRDP.

How do I fix CVE-2026-121964?

Upgrade to a fixed version.

Is CVE-2026-121964 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-121964 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-2026-121964, GHSA-m8gw-hjr2-4jc5, GHSA-q82v-5wjg-6h57, UBUNTU-CVE-2026-121964.