CVE-2026-91961
FreeRDP before 3.31.0 Denial of Service via URBDRC
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
FreeRDP before 3.31.0 Denial of Service via URBDRC
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
CVE-2026-91961- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-617
- Updated
- 2026-11-02
EUVDEUVD-2026-78637
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
EUVD-2026-78637- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-fqjp-p646-qwhr
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer...
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
GHSA-fqjp-p646-qwhr- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/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
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-617
- Updated
- 2026-11-02
NVD
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
CVE-2026-91961- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/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
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-617
- Updated
- 2026-11-02
OSV
FreeRDP before 3.31.0 Denial of Service via URBDRC
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
CVE-2026-91961- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-617
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-91961
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
DEBIAN-CVE-2026-91961- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/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
OSVUBUNTU-CVE-2026-91961
FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.
- Record
UBUNTU-CVE-2026-91961- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
freerdp2Debian:12 | All versions, plus listed versions 2.10.0+dfsg1-12.10.0+dfsg1-1.12.11.2+dfsg1-12.11.2+dfsg1-1.1~exp12.11.2+dfsg1-1.1~exp2 Show 8 moreShow less2.11.5+dfsg1-12.11.7+dfsg1-12.11.7+dfsg1-22.11.7+dfsg1-32.11.7+dfsg1-42.11.7+dfsg1-52.11.7+dfsg1-62.11.7+dfsg1-6~deb12u1 | None known |
freerdp3Debian: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 less3.16.0+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 |
freerdp3Debian: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 less3.17.1+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 |
freerdpUbuntu: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 |
freerdp2Ubuntu: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 less2.0.0~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 |
freerdpUbuntu: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 |
freerdp2Ubuntu: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 less2.2.0+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 |
freerdp2Ubuntu: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 less2.4.1+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 |
freerdp3Ubuntu: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 less3.5.1+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 |
freerdp2Ubuntu: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 less2.11.5+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 |
freerdp3Ubuntu: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 less3.20.2+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
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-91961 is a high vulnerability (CVSS 7.1) in Freerdp, published September 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.37%, the 31st percentile. Fixed in freerdp3 3.31.0+dfsg-1.
References
github.com/FreeRDP/FreeRDP/security/advisories/GHSA-w9qg-g24r-77f6
vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-urbdrc
nvd.nist.gov/vuln/detail/CVE-2026-91961
security-tracker.debian.org/tracker/CVE-2026-91961
ubuntu.com/security/CVE-2026-91961
cve.org/CVERecord?id=CVE-2026-91961