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.NET
.NET NuGet
Not in CISA KEV
HIGH severity

CVE-2019-0545 — Microsoft.NETCore.App

HIGH

CVE-2019-0545 is a high-severity (CVSS 7.5) Information Exposure vulnerability in Microsoft.NETCore.App. A fix is available for Microsoft.NETCore.App — see the affected versions and patch details below.

Exposure of Sensitive Information in System.Net.Http

Also known asGHSA-2xjx-v99w-gqf3
Published
Jan 8, 2019
Updated
Jul 8, 2026
Affected
2 pkgs
Patched
2 / 2
Exploits
None indexed
Exploitation data as of Sep 18, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
9.6%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs95th percentile — riskier than 95% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

CVE-2019-0545 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

2 pkgs affected
.NETMicrosoft.NETCore.App.NETMicrosoft.NETCore.App

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

An information disclosure vulnerability exists in .NET Framework and .NET Core which allows bypassing Cross-origin Resource Sharing (CORS) configurations, aka ".NET Framework Information Disclosure Vulnerability." This affects Microsoft .NET Framework 2.0, Microsoft .NET Framework 3.0, Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2, Microsoft .NET Framework 4.5.2, Microsoft .NET Framework 4.6, Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2, Microsoft .NET Framework 4.7/4.7.1/4.7.2, .NET Core 2.1, Microsoft .NET Framework 4.7.1/4.7.2, Microsoft .NET Framework 3.5, Microsoft .NET Framework 3.5.1, Microsoft .NET Framework 4.6/4.6.1/4.6.2, .NET Core 2.2, Microsoft .NET Framework 4.7.2.

Affected Packages

2 total 2 fixed
EcosystemPackageVulnerable rangeFix
.NETNuGetMicrosoft.NETCore.App≥ 2.1.0&&< 2.1.72.1.7dotnet add package Microsoft.NETCore.App --version 2.1.7
.NETNuGetMicrosoft.NETCore.App≥ 2.2.0&&< 2.2.12.2.1dotnet add package Microsoft.NETCore.App --version 2.2.1

Detection & mitigation playbook

Open-source dependency

  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Microsoft.NETCore.App, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update Microsoft.NETCore.App to 2.1.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-0545 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2019-0545 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2019-0545. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate
ProductFixed inAdvisory
.NET Core on Red Hat Enterprise Linuxrh-dotnet21-0:2.1-6.el7RHSA-2019:0040

Frequently Asked Questions

An information disclosure vulnerability exists in .NET Framework and .NET Core which allows bypassing Cross-origin Resource Sharing (CORS) configurations, aka ".NET Framework Information Disclosure Vulnerability." This affects Microsoft .NET Framework 2.0, Microsoft .NET Framework 3.0, Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2, Microsoft .NET Framework 4.5.2, Microsoft .NET Framework 4.6, Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2, Microsoft .NET Framework 4.7/4.7.1/4.7.2, .NET Core 2.1, Microsoft .NET Framework 4.7.1/4.7.2, Microsoft .NET Framework 3.5, Microsoft .NET Frame
O3 Security · Impact-Aware SCA

Is CVE-2019-0545 in your dependencies?

O3 Security finds CVE-2019-0545 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works
CVE-2019-0545: Microsoft.NETCore (High 7.5) | O3 Security