Every CVE Search/ Get API key

CVE-2026-91949

FreeRDP 3.0.0 through 3.30.0 Protocol Negotiation Bypass

9.2 CriticalFix available

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.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
High
Integrity
Low
Availability
None

Exploit likelihood

0.58%Up 0.1 points since Sep 16, 2026
90%50%10%1%

What each source reports

CVE List Score used 9.2

FreeRDP 3.0.0 through 3.30.0 Protocol Negotiation Bypass

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.

Record
CVE-2026-91949
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Weakness
CWE-693
Updated
2026-11-02
EUVDEUVD-2026-78806 9.2

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.

Record
EUVD-2026-78806
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N
Updated
2026-11-02
GitHub AdvisoriesGHSA-hcpv-8ff6-4xx8 9.2

FreeRDP server versions before 3.31.0 contain a protocol negotiation bypass vulnerability that...

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.

Record
GHSA-hcpv-8ff6-4xx8
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Weakness
CWE-693
Updated
2026-11-02
NVD 9.2

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.

Record
CVE-2026-91949
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Weakness
CWE-693
Updated
2026-11-02
OSV 9.2

FreeRDP 3.0.0 through 3.30.0 Protocol Negotiation Bypass

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.

Record
CVE-2026-91949
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N
Weakness
CWE-693
Updated
2026-11-02
OSVDEBIAN-CVE-2026-91949 9.2

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.

Record
DEBIAN-CVE-2026-91949
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Updated
2026-11-02
Show 5 moreShow less
OSVRHSA-2026:73979 9.3

Red Hat Security Advisory: freerdp security update

Record
RHSA-2026:73979
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Updated
2026-11-02
OSVRHSA-2026:74471 9.3

Red Hat Security Advisory: freerdp security update

Record
RHSA-2026:74471
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Updated
2026-11-02
OSVRLSA-2026:73979 9.3

Critical: freerdp security update

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. The xfreerdp client can connect to RDP servers such as Microsoft Windows machines, xrdp, and VirtualBox.

Security Fix(es):

  • freerdp: FreeRDP 3.0.0 through 3.30.0 Protocol Negotiation Bypass (CVE-2026-91949)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Record
RLSA-2026:73979
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Updated
2026-11-02
OSVUBUNTU-CVE-2026-91949 9.2

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.

Record
UBUNTU-CVE-2026-91949
CVSS 4.0
9.2 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N
CVSS 3.1
9.3 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
Updated
2026-11-02
OSVALSA-2026:73979 No score

Critical: freerdp security update

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. The xfreerdp client can connect to RDP servers such as Microsoft Windows machines, xrdp, and VirtualBox.

Security Fix(es):

  • freerdp: FreeRDP 3.0.0 through 3.30.0 Protocol Negotiation Bypass (CVE-2026-91949)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Record
ALSA-2026:73979
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
freerdp
AlmaLinux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-devel
AlmaLinux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-libs
AlmaLinux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-server
AlmaLinux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
libwinpr
AlmaLinux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
libwinpr-devel
AlmaLinux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp3
Debian:13
 All versions, plus listed versions
3.15.0+dfsg-2.13.15.0+dfsg-2.1+deb13u13.15.0+dfsg-2.1+deb13u23.15.0+dfsg-2.1+deb13u33.16.0+dfsg-1
Show 42 moreShow less
3.16.0+dfsg-23.17.0+dfsg-13.17.1+dfsg-13.17.1+dfsg-23.17.2+dfsg-13.17.2+dfsg-23.17.2+dfsg-33.18.0+dfsg-13.19.0+dfsg-13.19.1+dfsg-13.20.0+dfsg-13.20.2+dfsg-13.21.0+dfsg-13.22.0+dfsg-13.22.0+dfsg-1~bpo13+03.22.0+dfsg-1~bpo13+13.22.0+dfsg-33.23.0+dfsg-13.23.0+dfsg-1~bpo13+13.24.0+dfsg-13.24.0+dfsg-23.24.1+dfsg-13.24.2+dfsg-13.24.2+dfsg-1~bpo13+13.25.0+dfsg-13.25.0+dfsg-23.25.0+dfsg-33.25.0+dfsg-43.25.0+dfsg-53.26.0+dfsg-13.26.0+dfsg-1~bpo13+13.27.0+dfsg-13.27.1+dfsg-13.28.0+dfsg-13.28.0+dfsg-23.29.0+dfsg-13.30.0+dfsg-13.30.0+dfsg-1~bpo13+13.31.0+dfsg-13.31.1+dfsg-13.31.1+dfsg-1~bpo13+13.32.0+dfsg-1
 None known
freerdp3
Debian:14
 before 3.31.0+dfsg-1, plus listed versions
3.15.0+dfsg-2.13.16.0+dfsg-13.16.0+dfsg-23.17.0+dfsg-13.17.1+dfsg-1
Show 35 moreShow less
3.17.1+dfsg-23.17.2+dfsg-13.17.2+dfsg-23.17.2+dfsg-33.18.0+dfsg-13.19.0+dfsg-13.19.1+dfsg-13.20.0+dfsg-13.20.2+dfsg-13.21.0+dfsg-13.22.0+dfsg-13.22.0+dfsg-1~bpo13+03.22.0+dfsg-1~bpo13+13.22.0+dfsg-33.23.0+dfsg-13.23.0+dfsg-1~bpo13+13.24.0+dfsg-13.24.0+dfsg-23.24.1+dfsg-13.24.2+dfsg-13.24.2+dfsg-1~bpo13+13.25.0+dfsg-13.25.0+dfsg-23.25.0+dfsg-33.25.0+dfsg-43.25.0+dfsg-53.26.0+dfsg-13.26.0+dfsg-1~bpo13+13.27.0+dfsg-13.27.1+dfsg-13.28.0+dfsg-13.28.0+dfsg-23.29.0+dfsg-13.30.0+dfsg-13.30.0+dfsg-1~bpo13+1
3.31.0+dfsg-1
freerdp
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-debuginfo
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
Show 29 moreShow less
Affected packages
PackageAffectedFixed
freerdp-debugsource
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-libs
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-libs-debuginfo
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-server-debuginfo
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
libwinpr
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
libwinpr-debuginfo
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-devel
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp-server
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
libwinpr-devel
Red Hat:enterprise_linux:10.2
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-debuginfo
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-debugsource
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-libs
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-libs-debuginfo
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-server-debuginfo
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
libwinpr
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
libwinpr-debuginfo
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-devel
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp-server
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
libwinpr-devel
Red Hat:enterprise_linux_eus:10.0
From an advisory covering 2 CVEs
 before 2:3.10.3-3.el10_0.18
2:3.10.3-3.el10_0.18
freerdp
Rocky Linux:10
 before 2:3.10.3-12.el10_2.13
2:3.10.3-12.el10_2.13
freerdp
Ubuntu:16.04:LTS
 All versions, plus listed versions
1.1.0~git20140921.1.440916e+dfsg1-5ubuntu11.1.0~git20140921.1.440916e+dfsg1-5ubuntu1.21.1.0~git20140921.1.440916e+dfsg1-5ubuntu1.31.1.0~git20140921.1.440916e+dfsg1-5ubuntu1.4
 None known
freerdp2
Ubuntu:Pro:18.04:LTS
 All versions, plus listed versions
2.0.0~git20170725.1.1648deb+dfsg1-12.0.0~git20170725.1.1648deb+dfsg1-52.0.0~git20170725.1.1648deb+dfsg1-5ubuntu12.0.0~git20170725.1.1648deb+dfsg1-5ubuntu22.0.0~git20170725.1.1648deb+dfsg1-6
Show 14 moreShow less
2.0.0~git20170725.1.1648deb+dfsg1-6build12.0.0~git20170725.1.1648deb+dfsg1-72.0.0~git20170725.1.1648deb+dfsg1-7ubuntu0.12.1.1+dfsg1-0ubuntu0.18.04.12.2.0+dfsg1-0ubuntu0.18.04.12.2.0+dfsg1-0ubuntu0.18.04.22.2.0+dfsg1-0ubuntu0.18.04.32.2.0+dfsg1-0ubuntu0.18.04.42.2.0+dfsg1-0ubuntu0.18.04.4+esm12.2.0+dfsg1-0ubuntu0.18.04.4+esm22.2.0+dfsg1-0ubuntu0.18.04.4+esm32.2.0+dfsg1-0ubuntu0.18.04.4+esm42.2.0+dfsg1-0ubuntu0.18.04.4+esm52.2.0+dfsg1-0ubuntu0.18.04.4+esm6
 None known
freerdp
Ubuntu:18.04:LTS
 All versions, plus listed versions
1.1.0~git20140921.1.440916e+dfsg1-15ubuntu11.1.0~git20140921.1.440916e+dfsg1-15ubuntu1.18.04.11.1.0~git20140921.1.440916e+dfsg1-15ubuntu1.18.04.2
 None known
freerdp2
Ubuntu:Pro:20.04:LTS
 All versions, plus listed versions
2.0.0~git20190204.1.2693389a+dfsg1-12.0.0~git20190204.1.2693389a+dfsg1-22.0.0~git20190204.1.2693389a+dfsg1-2build12.0.0~git20190204.1.2693389a+dfsg1-2build22.1.1+dfsg1-0ubuntu0.20.04.1
Show 12 moreShow less
2.2.0+dfsg1-0ubuntu0.20.04.12.2.0+dfsg1-0ubuntu0.20.04.22.2.0+dfsg1-0ubuntu0.20.04.32.2.0+dfsg1-0ubuntu0.20.04.42.2.0+dfsg1-0ubuntu0.20.04.52.2.0+dfsg1-0ubuntu0.20.04.62.6.1+dfsg1-0ubuntu0.20.04.12.6.1+dfsg1-0ubuntu0.20.04.22.6.1+dfsg1-0ubuntu0.20.04.2+esm12.6.1+dfsg1-0ubuntu0.20.04.2+esm22.6.1+dfsg1-0ubuntu0.20.04.2+esm32.6.1+dfsg1-0ubuntu0.20.04.2+esm4
 None known
freerdp2
Ubuntu:22.04:LTS
 All versions, plus listed versions
2.3.0+dfsg1-2build12.3.0+dfsg1-2ubuntu12.3.0+dfsg1-2ubuntu22.4.1+dfsg1-12.4.1+dfsg1-1ubuntu1
Show 18 moreShow less
2.4.1+dfsg1-1ubuntu22.5.0+dfsg1-12.6.0+dfsg1-12.6.1+dfsg1-12.6.1+dfsg1-32.6.1+dfsg1-3ubuntu12.6.1+dfsg1-3ubuntu22.6.1+dfsg1-3ubuntu2.12.6.1+dfsg1-3ubuntu2.22.6.1+dfsg1-3ubuntu2.32.6.1+dfsg1-3ubuntu2.42.6.1+dfsg1-3ubuntu2.52.6.1+dfsg1-3ubuntu2.62.6.1+dfsg1-3ubuntu2.72.6.1+dfsg1-3ubuntu2.82.6.1+dfsg1-3ubuntu2.92.6.1+dfsg1-3ubuntu2.102.6.1+dfsg1-3ubuntu2.11
 None known
freerdp3
Ubuntu:24.04:LTS
 before 3.31.0+dfsg-0ubuntu0.24.04.1, plus listed versions
3.4.0+dfsg1-0ubuntu23.4.0+dfsg1-0ubuntu33.4.0+dfsg1-0ubuntu43.5.0+dfsg1-0ubuntu13.5.1+dfsg1-0ubuntu1
Show 7 moreShow less
3.5.1+dfsg1-0ubuntu1.13.5.1+dfsg1-0ubuntu1.23.5.1+dfsg1-0ubuntu1.43.5.1+dfsg1-0ubuntu1.53.5.1+dfsg1-0ubuntu1.63.30.0+dfsg-0ubuntu0.24.04.13.30.0+dfsg-0ubuntu0.24.04.2
3.31.0+dfsg-0ubuntu0.24.04.1
freerdp2
Ubuntu:Pro:24.04:LTS
 All versions, plus listed versions
2.10.0+dfsg1-1.1ubuntu12.11.2+dfsg1-12.11.2+dfsg1-1build12.11.2+dfsg1-1build32.11.5+dfsg1-1build1
Show 7 moreShow less
2.11.5+dfsg1-1build22.11.5+dfsg1-1ubuntu0.1~esm12.11.5+dfsg1-1ubuntu0.1~esm22.11.5+dfsg1-1ubuntu0.1~esm32.11.5+dfsg1-1ubuntu0.1~esm42.11.5+dfsg1-1ubuntu0.1~esm52.11.5+dfsg1-1ubuntu0.1~esm6
 None known
freerdp3
Ubuntu:26.04:LTS
 before 3.31.0+dfsg-0ubuntu0.26.04.1, plus listed versions
3.16.0+dfsg-23.18.0+dfsg-1ubuntu13.19.0+dfsg-13.19.1+dfsg-13.20.0+dfsg-1
Show 8 moreShow less
3.20.2+dfsg-13.21.0+dfsg-13.22.0+dfsg-13.24.1+dfsg-1ubuntu13.24.2+dfsg-1ubuntu13.24.2+dfsg-1ubuntu1.13.30.0+dfsg-0ubuntu0.26.04.13.30.0+dfsg-0ubuntu0.26.04.2
3.31.0+dfsg-0ubuntu0.26.04.1

History

History
RecordedChangedSources
affected, facts
first indexedCVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-91949 is a critical vulnerability (CVSS 9.2) in Freerdp, published September 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.58%, the 47th percentile. Fixed in freerdp 2:3.10.3-12.el10_2.13.

References

Show 21 moreShow less
Pages All vulnerabilities Browse Docs Sources Guide Get API key
MoveEnter Open