How severe is CVE-2014-0253?

CVE-2014-0253 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2014-0253 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 39% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2014-0253?

CVE-2014-0253 primarily affects Microsoft .net Framework. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2014-0253?

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

When was CVE-2014-0253 published?

CVE-2014-0253 was published on 2014-02-12 and last updated on 2026-06-17.

CVE-2014-0253

CVE-2014-0253 is a medium-severity vulnerability in Microsoft .net Framework with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 39% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 39% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft .net Framework
Published: 2014-02-12
Last modified: 2026-06-17

Description

Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.5, 3.5.1, 4, 4.5, and 4.5.1 does not properly determine TCP connection states, which allows remote attackers to cause a denial of service (ASP.NET daemon hang) via crafted HTTP requests that trigger persistent resource consumption for a (1) stale or (2) closed connection, as exploited in the wild in February 2014, aka "POST Request DoS Vulnerability."

Frequently asked questions

What is CVE-2014-0253?: Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.5, 3.5.1, 4, 4.5, and 4.5.1 does not properly determine TCP connection states, which allows remote attackers to cause a denial of service (ASP.NET daemon hang) via crafted HTTP requests that trigger persistent resource consumption for a (1) stale or (2) closed connection, as exploited in the wild in February 2014, aka "POST Request DoS Vulnerability."
How severe is CVE-2014-0253?: CVE-2014-0253 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2014-0253 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 39% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2014-0253?: CVE-2014-0253 primarily affects Microsoft .net Framework. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2014-0253?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2014-0253 published?: CVE-2014-0253 was published on 2014-02-12 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:microsoft:.net_framework:1.1:sp1:*:*:*:*:*:*
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:3.5.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.5:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.5.1:*:*:*:*:*:*:*

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