Vulnerability in Freerdp
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (31.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-w9qg-g24r-77f6 (vendor-advisory, Vendor Advisory)
- www.vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-urbdrc (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-91961?
- CVE-2026-91961 is a medium-severity vulnerability in Freerdp, classified under Reachable Assertion. CVSS score: 6.5/10. Published 2026-09-15.
- How severe is CVE-2026-91961?
- Medium severity. CVSS v3 base score is 6.5 out of 10.