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 Fou…

published 2013-12-11 12y ago modified 2026-06-16 4mo ago also EUVD-2013-4884

cvss: 4.3; version 2.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 11.7%; EPSS 11.7% chance of exploitation in 30 days, percentile 96%
public exploits: 0; none known

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."

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Exploit prediction

11.69% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

docs.microsoft.com /en-us/security-updates/securitybulletins/2013/ms13-103
vendor-advisory
securitytracker.com /id/1029463
vdb-entry

Sources

CVE List CVE-2013-5042
NVD CVE-2013-5042

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