Out-of-bounds Read in Freerdp
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.
Vulnerability class: Buffer Overflow
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 (33.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.2% 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-hg4r-vv53-vwf8 (Exploit, vendor-advisory, Mitigation, Vendor Advisory)
- www.vulncheck.com/advisories/freerdp-before-3.31.0-out-of-bounds-read-via-urbdrc (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-91956?
- CVE-2026-91956 is a medium-severity vulnerability in Freerdp, classified under Out-of-bounds Read. CVSS score: 6.5/10. Published 2026-09-15.
- How severe is CVE-2026-91956?
- Medium severity. CVSS v3 base score is 6.5 out of 10.