6.5Medium
CVE-2026-91956
FreeRDP before 3.31.0 contains an out-of-bounds read vulnerability in the URBDRC channel's func_get_ep_desc function that indexes interface arrays by position instead of protocol field InterfaceNumber. A malicious RDP server can send a crafted SELECT_CONFIGURATION message with permuted InterfaceNumber values to read past allocated heap memory and crash the client.
What this means for your business
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 27% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 6.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H- CVSS v4
- 7.1
- Weakness
- CWE-125
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-15
- Last modified
- 2026-09-16
- Sources
- NVD