How severe is CVE-2013-3861?

CVE-2013-3861 has a CVSS 2.0 base score of 7.8, rated high severity.

Is CVE-2013-3861 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 83% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-3861?

CVE-2013-3861 primarily affects Microsoft .net Framework. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-3861?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2013-3861 published?

CVE-2013-3861 was published on 2013-10-09 and last updated on 2026-06-16.

CVE-2013-3861

CVE-2013-3861 is a high-severity vulnerability in Microsoft .net Framework with a CVSS 2.0 base score of 7.8. Its EPSS exploit-prediction score of 83% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 2.0 base score 7.8)
EPSS exploit prediction: 83% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft .net Framework
Published: 2013-10-09
Last modified: 2026-06-16

Description

Microsoft .NET Framework 2.0 SP2, 3.5, 3.5 SP1, 3.5.1, 4, and 4.5 allows remote attackers to cause a denial of service (application crash or hang) via crafted character sequences in JSON data, aka "JSON Parsing Vulnerability."

Frequently asked questions

What is CVE-2013-3861?: Microsoft .NET Framework 2.0 SP2, 3.5, 3.5 SP1, 3.5.1, 4, and 4.5 allows remote attackers to cause a denial of service (application crash or hang) via crafted character sequences in JSON data, aka "JSON Parsing Vulnerability."
How severe is CVE-2013-3861?: CVE-2013-3861 has a CVSS 2.0 base score of 7.8, rated high severity.
Is CVE-2013-3861 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 83% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-3861?: CVE-2013-3861 primarily affects Microsoft .net Framework. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-3861?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2013-3861 published?: CVE-2013-3861 was published on 2013-10-09 and last updated on 2026-06-16.

References

Affected products (6)

cpe:2.3:a:microsoft:.net_framework:2.0:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:3.5:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:3.5:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:3.5.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.5:*:*:*:*:*:*:*

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