CVE-2013-5042: Microsoft ASP.NET Signalr

Medium severity, CVSS 4.3. EPSS: 11.7% chance of exploitation in the next 30 days.

Cross-site scripting (XSS) vulnerability in Microsoft ASP.NET SignalR 1.1.x before 1.1.4 and 2.0.x before 2.0.1, and Visual Studio Team Foundation Server 2013, allows remote attackers to inject arbitrary web script or HTML via crafted Forever Frame transport protocol data, aka "SignalR XSS Vulnerability."

Affected products

• Microsoft ASP.NET Signalr: version 1.1.0 only; version 1.1.1 only; version 1.1.2 only; version 1.1.3 only; version 2.0.0 only
• Microsoft Visual Studio Team Foundation Server: version 2013 only

Published 2013-12-11. Last modified 2026-06-16.