CVE-2026-91949 FreeRDP 3.0.0 through 3.30.0 Protocol Negotiation Bypass
Unauthenticated attackers can bypass RDSTLS transport restrictions in FreeRDP servers by manipulating protocol negotiation, allowing unauthorized TLS connections.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-91949?
CVE-2026-91949 is a critical vulnerability in Freerdp Freerdp, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-693
Which versions are affected by CVE-2026-91949?
It affects 1 product.
Linux distribution packages (18)
freerdp AlmaLinux:10 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-devel AlmaLinux:10 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-libs AlmaLinux:10 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-server AlmaLinux:10 | All versions | 2:3.10.3-12.el10_2.13 |
libwinpr AlmaLinux:10 | All versions | 2:3.10.3-12.el10_2.13 |
libwinpr-devel AlmaLinux:10 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-debugsource Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-devel Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-libs Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-libs-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-server Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp-server-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
libwinpr Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
libwinpr-debuginfo Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
libwinpr-devel Red Hat:enterprise_linux:10.2 | All versions | 2:3.10.3-12.el10_2.13 |
freerdp Rocky Linux:10 | All versions | 2:3.10.3-12.el10_2.13 |
Products include Freerdp Freerdp.
How do I fix CVE-2026-91949?
Upgrade to a fixed version.
Is CVE-2026-91949 being exploited?
There is no known exploitation of CVE-2026-91949 in the wild and no public exploit code.
Other vulnerabilities in Freerdp Freerdp
- CVE-2021-37594 Other in n/a
- CVE-2021-37595 Other in n/a
- CVE-2026-67305 FreeRDP Windows Client before 3.29.0 Heap Buffer Overflow via Cliprdr
- CVE-2026-66402 FreeRDP before 3.29.0 TLS Certificate Identity Validation Bypass
- CVE-2026-67289 FreeRDP before 3.29.0 HTTP Proxy Request Injection via Redirection
Sources
Also known as ALSA-2026:73979, DEBIAN-CVE-2026-91949, GHSA-hcpv-8ff6-4xx8, GHSA-x7v6-xfx3-52j6, RHSA-2026:73979, RLSA-2026:73979 and 1 more.