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


- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 4 Nov 2026
- **Updated:** 4 Nov 2026
- **Also known as:** DEBIAN-CVE-2026-121964, GHSA-m8gw-hjr2-4jc5, GHSA-q82v-5wjg-6h57, UBUNTU-CVE-2026-121964

## 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 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-121964?

It affects 1 product.


Products: 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](https://insights.sbomify.com/CVE-2024-32658/): FreeRDP ExtractRunLengthRegular* out of bound read (critical 9.8)
- [CVE-2024-32659](https://insights.sbomify.com/CVE-2024-32659/): freerdp_image_copy out of bound read (critical 9.8)
- [CVE-2024-32039](https://insights.sbomify.com/CVE-2024-32039/): FreeRDP Integer overflow & OutOfBound Write in clear_decompress_residual_data (critical 9.8)
- [CVE-2024-32041](https://insights.sbomify.com/CVE-2024-32041/): FreeRDP OutOfBound Read in zgfx_decompress_segment (critical 9.8)
- [CVE-2024-32458](https://insights.sbomify.com/CVE-2024-32458/): FreeRDP Out-Of-Bounds Read in planar_skip_plane_rle (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-121964 and fix it if it is affected.

What it is: CVE-2026-121964 is a high-severity vulnerability in FreeRDP, published on 4 Nov 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-121964 exists.

Affected product: FreeRDP. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-121964/ (Markdown: https://insights.sbomify.com/CVE-2026-121964/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-121964
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-121964
- OSV: https://osv.dev/vulnerability/CVE-2026-121964

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-121964/
Summaries are generated and may contain mistakes; the official description above is the record.