# CVE-2026-91949: freerdp3: FreeRDP server versions before 3.31.0 contain a protocol negotiation bypass vulnerability that allows unauthenticated...

CVE-2026-91949 is fixed in 34 products on 1 platform, first by RHSA-2026:74471, released September 11, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-91949
- Priority: High
- CVSS: 9.3 (Medium)
- EPSS: 0.0058
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 14, 2026

## Description

FreeRDP server versions before 3.31.0 contain a protocol negotiation bypass vulnerability that allows unauthenticated attackers to establish RDSTLS connections despite server policy disabling them. Attackers can send incompatible protocol requests, receive negotiation failures, then complete TLS handshake and enter RDSTLS to bypass pre-authentication transport restrictions.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | freerdp RHEL 10 | 3.10.3-3.el10_0.18 | [RHSA-2026:74471](https://patchblox.com/security/data/fix/linux/rhsa-2026-74471.md) | Sep 11, 2026 |
| Linux | freerdp almalinux 10 | 2:3.10.3-12.el10_2.13 | [ALSA-2026:73979](https://patchblox.com/security/data/fix/linux/alsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp ol 10 | 2:3.10.3-12.el10_2.13 | [ELSA-2026-73979](https://patchblox.com/security/data/fix/linux/elsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp rocky 10 | 2:3.10.3-12.el10_2.13 | [RLSA-2026:73979](https://patchblox.com/security/data/fix/linux/rlsa-2026-73979.md) | Oct 2, 2026 |
| Linux | freerdp-debuginfo amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-debugsource amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-devel almalinux 10 | 2:3.10.3-12.el10_2.13 | [ALSA-2026:73979](https://patchblox.com/security/data/fix/linux/alsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp-devel amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-devel ol 10 | 2:3.10.3-12.el10_2.13 | [ELSA-2026-73979](https://patchblox.com/security/data/fix/linux/elsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp-libs almalinux 10 | 2:3.10.3-12.el10_2.13 | [ALSA-2026:73979](https://patchblox.com/security/data/fix/linux/alsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp-libs amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-libs ol 10 | 2:3.10.3-12.el10_2.13 | [ELSA-2026-73979](https://patchblox.com/security/data/fix/linux/elsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp-libs-debuginfo amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-proxy Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp-proxy 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp-proxy-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp-proxy-modules Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp-proxy-modules 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp-proxy-modules-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp-sdl Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp-sdl 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp-sdl-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp-server almalinux 10 | 2:3.10.3-12.el10_2.13 | [ALSA-2026:73979](https://patchblox.com/security/data/fix/linux/alsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp-server amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-server ol 10 | 2:3.10.3-12.el10_2.13 | [ELSA-2026-73979](https://patchblox.com/security/data/fix/linux/elsa-2026-73979.md) | Sep 30, 2026 |
| Linux | freerdp-server-debuginfo amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | freerdp-shadow-x11 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp-shadow-x11 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp-shadow-x11-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp-wayland Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp-wayland 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp-wayland-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp-x11 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp-x11 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp-x11-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp3 Debian 14 | 3.31.0+dfsg-1 | [DEBIAN-CVE-2026-91949](https://patchblox.com/security/data/fix/linux/debian-cve-2026-91949.md) | Sep 17, 2026 |
| Linux | freerdp3-proxy Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp3-proxy 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp3-proxy-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp3-proxy-modules Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp3-proxy-modules 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp3-proxy-modules-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp3-sdl Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp3-sdl 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp3-sdl-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp3-shadow-x11 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [freerdp3-shadow-x11 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-freerdp3-shadow-x11-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | freerdp3-shadow-x11 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp3-shadow-x11 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp3-shadow-x11-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp3-wayland Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [freerdp3-wayland 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-freerdp3-wayland-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | freerdp3-wayland Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp3-wayland 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp3-wayland-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | freerdp3-x11 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [freerdp3-x11 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-freerdp3-x11-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | freerdp3-x11 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [freerdp3-x11 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-freerdp3-x11-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libfreerdp-client3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libfreerdp-client3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libfreerdp-client3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libfreerdp-client3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libfreerdp-client3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libfreerdp-client3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libfreerdp-server-proxy3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libfreerdp-server-proxy3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libfreerdp-server-proxy3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libfreerdp-server3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libfreerdp-server3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libfreerdp-server3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libfreerdp-server3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libfreerdp-server3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libfreerdp-server3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libfreerdp-shadow-subsystem3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libfreerdp-shadow-subsystem3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libfreerdp-shadow-subsystem3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libfreerdp-shadow-subsystem3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libfreerdp-shadow-subsystem3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libfreerdp-shadow-subsystem3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libfreerdp-shadow3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libfreerdp-shadow3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libfreerdp-shadow3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libfreerdp-shadow3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libfreerdp-shadow3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libfreerdp-shadow3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libfreerdp3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libfreerdp3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libfreerdp3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libfreerdp3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libfreerdp3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libfreerdp3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libwinpr almalinux 10 | 2:3.10.3-12.el10_2.13 | [ALSA-2026:73979](https://patchblox.com/security/data/fix/linux/alsa-2026-73979.md) | Sep 30, 2026 |
| Linux | libwinpr amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | libwinpr ol 10 | 2:3.10.3-12.el10_2.13 | [ELSA-2026-73979](https://patchblox.com/security/data/fix/linux/elsa-2026-73979.md) | Sep 30, 2026 |
| Linux | libwinpr-debuginfo amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | libwinpr-devel almalinux 10 | 2:3.10.3-12.el10_2.13 | [ALSA-2026:73979](https://patchblox.com/security/data/fix/linux/alsa-2026-73979.md) | Sep 30, 2026 |
| Linux | libwinpr-devel amzn 2023 | 2:3.31.0-1.amzn2023 | [ALAS2023-2026-2142](https://patchblox.com/security/data/fix/linux/alas2023-2026-2142.md) | Sep 14, 2026 |
| Linux | libwinpr-devel ol 10 | 2:3.10.3-12.el10_2.13 | [ELSA-2026-73979](https://patchblox.com/security/data/fix/linux/elsa-2026-73979.md) | Sep 30, 2026 |
| Linux | libwinpr-tools3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libwinpr-tools3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libwinpr-tools3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libwinpr-tools3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libwinpr-tools3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libwinpr-tools3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | libwinpr3-3 Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [libwinpr3-3 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libwinpr3-3-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | libwinpr3-3 Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [libwinpr3-3 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-libwinpr3-3-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | winpr-utils Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [winpr-utils 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-winpr-utils-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |
| Linux | winpr3-utils Ubuntu 24.04.5 LTS (noble) | 3.31.0+dfsg-0ubuntu0.24.04.1 | [winpr3-utils 3.31.0+dfsg-0ubuntu0.24.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-winpr3-utils-3.31.0-dfsg-0ubuntu0.24.04.1.md) | Sep 14, 2026 |
| Linux | winpr3-utils Ubuntu 26.04.1 LTS (resolute) | 3.31.0+dfsg-0ubuntu0.26.04.1 | [winpr3-utils 3.31.0+dfsg-0ubuntu0.26.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-winpr3-utils-3.31.0-dfsg-0ubuntu0.26.04.1.md) | Sep 15, 2026 |

---

Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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