CVE-2008-5911: Realnetworks Helix Server

High severity, CVSS 10.0. EPSS: 6.2% chance of exploitation in the next 30 days.

Multiple buffer overflows in RealNetworks Helix Server and Helix Mobile Server 11.x before 11.1.8 and 12.x before 12.0.1 allow remote attackers to (1) cause a denial of service via three crafted RTSP SETUP commands, or execute arbitrary code via (2) an NTLM authentication request with malformed base64-encoded data, (3) an RTSP DESCRIBE command, or (4) a DataConvertBuffer request.

Affected products

• Realnetworks Helix Server: version 11.0 only; version 12.0.0 only
• Realnetworks Helix Server Mobile: version 11.0 only; version 12.0.0 only

Published 2009-01-20. Last modified 2026-06-16.