CVE-2026-121404

EUVD-2026-115936
FreeRDP before 3.32.2 contains a denial of service vulnerability in the shadow server that allows authenticated RDP clients to spin server threads by sending zero-length drdynvc DATA PDUs. Attackers can send empty DATA messages on opened audin or rdpgfx channels, so that FreeRDP_WTSVirtualChannelRead never consumes them, consuming full CPU cores until disconnect.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.5 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
freerdpfreerdp
𝑥
< 3.32.2
𝑥
= Vulnerable software versions
Common Weakness Enumeration
References
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-fqcj-rwww-2498
https://www.vulncheck.com/advisories/freerdp-before-3.32.2-shadow-server-cpu-exhaustion-via-zero-length-dvc-data