How severe is CVE-2013-5042?

CVE-2013-5042 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2013-5042 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 12% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-5042?

CVE-2013-5042 primarily affects Microsoft Asp.net Signalr. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-5042?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2013-5042 published?

CVE-2013-5042 was published on 2013-12-11 and last updated on 2026-06-16.

CVE-2013-5042

CVE-2013-5042 is a medium-severity vulnerability in Microsoft Asp.net Signalr with a CVSS 2.0 base score of 4.3. Its EPSS exploit-prediction score of 12% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 12% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Microsoft Asp.net Signalr
Published: 2013-12-11
Last modified: 2026-06-16

Description

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."

Frequently asked questions

What is CVE-2013-5042?: 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."
How severe is CVE-2013-5042?: CVE-2013-5042 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2013-5042 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 12% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-5042?: CVE-2013-5042 primarily affects Microsoft Asp.net Signalr. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-5042?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-5042 published?: CVE-2013-5042 was published on 2013-12-11 and last updated on 2026-06-16.

References

Affected products (6)

cpe:2.3:a:microsoft:asp.net_signalr:1.1.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_signalr:1.1.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_signalr:1.1.2:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_signalr:1.1.3:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_signalr:2.0.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:visual_studio_team_foundation_server:2013:*:*:*:*:*:*:*

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