CVE-2026-91963: FreeRDP 2.0.0 through 3.30.0 Uninitialized Heap Memory Disclosure via urbdrc

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-15 · updated 2026-09-23
Weakness: CWE-457

Description

FreeRDP versions before 3.31.0 contain an uninitialized heap memory disclosure vulnerability in the urbdrc USB redirection channel. A malicious RDP server can induce failing USB transfers to read uninitialized heap memory from the client, defeating ASLR and enabling remote code execution when chained with memory corruption vulnerabilities.

Affected products

FreeRDP: from 2.0.0 before 3.31.0 — fixed in 3.31.0

How to fix

Upgrade to a fixed version: FreeRDP 3.31.0. Check the vendor advisory for mitigations.

References

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hw7p-5h2r-83gq
https://www.vulncheck.com/advisories/freerdp-2.0.0-through-3.30.0-uninitialized-heap-memory-disclosure-via-urbdrc
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hw7p-5h2r-83gq

Get alerted when CVE-2026-91963 or the next vulnerability affects your stack