# CVE-2018-0786: Improper Certificate Validation in Microsoft .NET Framework components > Attackers can bypass certificate validation in Microsoft .NET and PowerShell, potentially enabling man-in-the-middle attacks or trust violations. - **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 10 Jan 2018 - **Updated:** 16 Sep 2024 - **Also known as:** GHSA-jc8g-xhw5-6x46 ## What is CVE-2018-0786? CVE-2018-0786 is a high-severity vulnerability in Microsoft .Net Framework, published on 10 Jan 2018. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description Microsoft .NET Framework 2.0 SP2, 3.0 SP2, 3.5, 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, .NET Core 1.0 and 2.0, and PowerShell Core 6.0.0 allow a security feature bypass vulnerability due to the way certificates are validated, aka ".NET Security Feature Bypass Vulnerability." Weakness: CWE-295 (Improper Certificate Validation) ## Which versions are affected by CVE-2018-0786? 40 open source packages ship an affected version, including Microsoft.NETCore.UniversalWindowsPlatform, System.Private.ServiceModel and System.ServiceModel.Duplex. It affects 3 products. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 5.2.0 | 5.2.4 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 5.2.0 | 5.2.4 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 5.3.0 | 5.3.5 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 5.3.0 | 5.3.5 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 5.4.0 | 5.4.2 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 5.4.0 | 5.4.2 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 6.0.0 | 6.0.6 | | `Microsoft.NETCore.UniversalWindowsPlatform` | NuGet | From 6.0.0 | 6.0.6 | | `System.Private.ServiceModel` | NuGet | From 4.1.0 | 4.1.1 | | `System.Private.ServiceModel` | NuGet | From 4.1.0 | 4.1.1 | | `System.Private.ServiceModel` | NuGet | From 4.3.0 | 4.3.1 | | `System.Private.ServiceModel` | NuGet | From 4.3.0 | 4.3.1 | | `System.Private.ServiceModel` | NuGet | From 4.4.0 | 4.4.1 | | `System.Private.ServiceModel` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Duplex` | NuGet | From 4.0.1 | 4.0.2 | | `System.ServiceModel.Duplex` | NuGet | From 4.0.1 | 4.0.2 | | `System.ServiceModel.Duplex` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.Duplex` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.Duplex` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Duplex` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Http` | NuGet | From 4.1.0 | 4.1.1 | | `System.ServiceModel.Http` | NuGet | From 4.1.0 | 4.1.1 | | `System.ServiceModel.Http` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.Http` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.Http` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Http` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.NetTcp` | NuGet | From 4.1.0 | 4.1.1 | | `System.ServiceModel.NetTcp` | NuGet | From 4.1.0 | 4.1.1 | | `System.ServiceModel.NetTcp` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.NetTcp` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.NetTcp` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.NetTcp` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Primitives` | NuGet | From 4.1.0 | 4.1.1 | | `System.ServiceModel.Primitives` | NuGet | From 4.1.0 | 4.1.1 | | `System.ServiceModel.Primitives` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.Primitives` | NuGet | From 4.3.0 | 4.3.1 | | `System.ServiceModel.Primitives` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Primitives` | NuGet | From 4.4.0 | 4.4.1 | | `System.ServiceModel.Security` | NuGet | From 4.0.1 | 4.0.2 | | `System.ServiceModel.Security` | NuGet | From 4.0.1 | 4.0.2 | Products: Microsoft .Net Core, Microsoft .Net Framework, Microsoft Powershell Core. ## How do I fix CVE-2018-0786? Upgrade Microsoft.NETCore.UniversalWindowsPlatform to a fixed version for your release line: 5.2.4, 5.3.5, 5.4.2 or 6.0.6. ## Is CVE-2018-0786 being exploited? There is no known exploitation of CVE-2018-0786 in the wild and no public exploit code. ## Other vulnerabilities in Microsoft .Net Framework - [CVE-2020-1147](https://insights.sbomify.com/CVE-2020-1147/): Microsoft .NET Framework, SharePoint, and Visual Studio Remote Code Execution (high 7.8, exploited in the wild) - [CVE-2020-0605](https://insights.sbomify.com/CVE-2020-0605/): Code injection in .NET Core (high 8.8) - [CVE-2020-0606](https://insights.sbomify.com/CVE-2020-0606/): Remote code execution in Microsoft.WindowsDesktop.App.Ref (high 8.8) - [CVE-2019-1301](https://insights.sbomify.com/CVE-2019-1301/): High severity vulnerability that affects System.Management.Automation (high 7.5) - [CVE-2019-0820](https://insights.sbomify.com/CVE-2019-0820/): Regular Expression Denial of Service in System.Text.RegularExpressions (high 7.5) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2018-0786 and fix it if it is affected. What it is: CVE-2018-0786 is a high-severity vulnerability in Microsoft .Net Framework, published on 10 Jan 2018. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2018-0786 in the wild and no public exploit code. Affected packages and fixed versions: - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 5.2.0; fixed in 5.2.4 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 5.2.0; fixed in 5.2.4 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 5.3.0; fixed in 5.3.5 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 5.3.0; fixed in 5.3.5 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 5.4.0; fixed in 5.4.2 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 5.4.0; fixed in 5.4.2 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 6.0.0; fixed in 6.0.6 - Microsoft.NETCore.UniversalWindowsPlatform (NuGet): affected from 6.0.0; fixed in 6.0.6 - System.Private.ServiceModel (NuGet): affected from 4.1.0; fixed in 4.1.1 - System.Private.ServiceModel (NuGet): affected from 4.1.0; fixed in 4.1.1 - System.Private.ServiceModel (NuGet): affected from 4.3.0; fixed in 4.3.1 - System.Private.ServiceModel (NuGet): affected from 4.3.0; fixed in 4.3.1 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2018-0786/ (Markdown: https://insights.sbomify.com/CVE-2018-0786/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0786 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0786 - OSV: https://osv.dev/vulnerability/CVE-2018-0786 --- From sbomify Insights: https://insights.sbomify.com/CVE-2018-0786/ Summaries are generated and may contain mistakes; the official description above is the record.